Animated map provided by ZwiftHacks The London course’s “Classique” route takes you on some of the most famous London streets including Strand, The Mall, Constitution Hill, and Birdcage Walk. You ride by Trafalgar Square and Buckingham Palace. Route Basics Length: 5.5 km (3.4 miles) Elevation: 16 m (52‘) Lead-In: 5.6 km (3.5 miles) Map: London Restriction: none Achievement Badge: 110 XP The London course’s “Classique” route takes you on some of the most famous London streets including Strand, The Mall, Constitution Hill, and Birdcage Walk. You ride by Trafalgar Square and Buckingham Palace. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Keith Hill After Party

Animated map provided by ZwiftHacks London’s “Keith Hill After Party” is a custom route introduced for stage 3 of January 2019’s Tour de Zwift . Route Basics Length: 36.2 km (22.5 miles) Elevation: 431 m (1,414‘) Lead-In: 0.6 km (0.4 miles) Map: London Restriction: Event Only Achievement Badge: none London’s “Keith Hill After Party” is a custom route introduced for stage 3 of January 2019’s Tour de Zwift . See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Leith Hill After Party

Animated map provided by ZwiftHacks London’s “Leith Hill After Party” is an event-only route, meaning it is only available for group events. Very similar in profile to London’s “ Keith Hill After Party ” route, the Leith Hill version has an extra 5km of flat road before the finishing climb. Route Basics Length: 41.5 km (25.8 miles) Elevation: 435 m (1,427‘) Lead-In: 0.6 km (0.4 miles) Map: London Restriction: Event Only Achievement Badge: none London’s “Leith Hill After Party” is an event-only route, meaning it is only available for group events. Very similar in profile to London’s “ Keith Hill After Party ” route, the Leith Hill version has an extra 5km of flat road before the finishing climb. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks The London course’s “London 8” route covers the entire original London course by combining the “ London Loop ” and “ Classique ” routes. Route Basics Length: 20.3 km (12.6 miles) Elevation: 219 m (719‘) Lead-In: 0.6 km (0.4 miles) Map: London Restriction: none Achievement Badge: 410 XP The London course’s “London 8” route covers the entire original London course by combining the “ London Loop ” and “ Classique ” routes. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks Route Basics Length: 20.3 km (12.6 miles) Elevation: 219 m (719‘) Lead-In: 0.2 km (0.1 miles) Map: London Restriction: Event Only Achievement Badge: none See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks Released in October 2025 to host Zwift Unlocked events, London Calling covers all the same roads as Greatest London Flat , but with some extra riding in other directions and different start/finish lines. Route Basics Length: 31.2 km (19.4 miles) Elevation: 207 m (679‘) Lead-In: 0.5 km (0.3 miles) Map: London Restriction: none Achievement Badge: 625 XP Released in October 2025 to host Zwift Unlocked events, London Calling covers all the same roads as Greatest London Flat , but with some extra riding in other directions and different start/finish lines. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks Unveiled for Tour de Zwift 2025, this route travels a flat, clockwise loop on either side of the Thames. It’s unique in that the start/finish line is at the start of the Tower Bridge. Route Basics Length: 11.99 km (7.5 miles) Elevation: 115 m (377‘) Lead-In: 0.39 km (0.2 miles) Map: London Restriction: none Achievement Badge: 240 XP Unveiled for Tour de Zwift 2025, this route travels a flat, clockwise loop on either side of the Thames. It’s unique in that the start/finish line is at the start of the Tower Bridge. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks The London course’s “London Loop” route takes you along the Thames and up to Trafalgar Square before heading down into the Underground and up Box Hill. Route Basics Length: 14.9 km (9.3 miles) Elevation: 231 m (758‘) Lead-In: 0.6 km (0.4 miles) Map: London Restriction: none Achievement Badge: 300 XP The London course’s “London Loop” route takes you along the Thames and up to Trafalgar Square before heading down into the Underground and up Box Hill. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks The reverse version of London’s first loop route , “London Loop Reverse” takes you up Fox Hill, then down Box Hill and along the Thames. Route Basics Length: 14.8 km (9.2 miles) Elevation: 231 m (758‘) Lead-In: 0.2 km (0.1 miles) Map: London Restriction: Event Only Achievement Badge: none The reverse version of London’s first loop route , “London Loop Reverse” takes you up Fox Hill, then down Box Hill and along the Thames. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks Released as a route for Zwift Games 2025, London Uprising starts and ends with select climbs up Fox and Box Hills, respectively. Here’s an interesting bit of Zwift trivia: this route is actually fully contained in the much longer London Pretzel , meaning many Zwifters will have completed the Strava segment several years before it became an official Zwift route. Route Basics Length: 20.5 km (12.7 miles) Elevation: 356 m (1,168‘) Lead-In: 0.3 km (0.2 miles) Map: London Restriction: none Achievement Badge: 420 XP Released as a route for Zwift Games 2025, London Uprising starts and ends with select climbs up Fox and Box Hills, respectively. Here’s an interesting bit of Zwift trivia: this route is actually fully contained in the much longer London Pretzel , meaning many Zwifters will have completed the Strava segment several years before it became an official Zwift route. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks London’s “Surrey Hills” route takes you on a complete tour of all the climbs on the London course, riding over each pass in both directions. Since the route keeps you almost entirely off of flat ground, you get a lot of climbing done in just over 44km. Route Basics Length: 39.2 km (24.4 miles) Elevation: 837 m (2,746‘) Lead-In: 5.1 km (3.2 miles) Map: London Restriction: none Achievement Badge: 820 XP London’s “Surrey Hills” route takes you on a complete tour of all the climbs on the London course, riding over each pass in both directions. Since the route keeps you almost entirely off of flat ground, you get a lot of climbing done in just over 44km. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks Route Basics Length: 5.4 km (3.4 miles) Elevation: 25 m (82‘) Lead-In: 7.6 km (4.7 miles) Map: London Restriction: Event Only Achievement Badge: 110 XP See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks At the time of its release, the “London Pretzel” route was the only route covering all London roads. In fact, it covered them all in both directions. The route leaves off newer additions to the London course, but it’s still a fun one if you’re looking for a longer ride with a mix of flat efforts broken up by two decent climb sections. Route Basics Length: 55.7 km (34.6 miles) Elevation: 571 m (1,873‘) Lead-In: 0.6 km (0.4 miles) Map: London Restriction: none Achievement Badge: 1100 XP At the time of its release, the “London Pretzel” route was the only route covering all London roads. In fact, it covered them all in both directions. The route leaves off newer additions to the London course, but it’s still a fun one if you’re looking for a longer ride with a mix of flat efforts broken up by two decent climb sections. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks The London course’s “PRL Full” route is meant to mimic the distance (but not the full course) of the real Prudential RideLondon-Surrey 100 event. Route Basics Length: 173 km (107.5 miles) Elevation: 2621 m (8,599‘) Lead-In: 0.5 km (0.3 miles) Map: London Restriction: none Achievement Badge: 3460 XP The London course’s “PRL Full” route is meant to mimic the distance (but not the full course) of the real Prudential RideLondon-Surrey 100 event. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks The London course’s “PRL Half” route is meant to mimic the distance (but not the full course) of the real Prudential RideLondon-Surrey 46. Route Basics Length: 69.1 km (42.9 miles) Elevation: 1009 m (3,310‘) Lead-In: 0.6 km (0.4 miles) Map: London Restriction: none Achievement Badge: 1380 XP The London course’s “PRL Half” route is meant to mimic the distance (but not the full course) of the real Prudential RideLondon-Surrey 46. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks London’s “Triple Loops” route is a large loop containing three more loops. First you hit the Greater London loop , then the Classique , then ride over Leith Hill to a loop which includes Box Hill. Descend Fox Hill, ride up through the Underground, then it’s a drag race to the finish. Route Basics Length: 40.9 km (25.4 miles) Elevation: 565 m (1,854‘) Lead-In: 0.5 km (0.3 miles) Map: London Restriction: none Achievement Badge: 810 XP London’s “Triple Loops” route is a large loop containing three more loops. First you hit the Greater London loop , then the Classique , then ride over Leith Hill to a loop which includes Box Hill. Descend Fox Hill, ride up through the Underground, then it’s a drag race to the finish. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks London’s “Greater London 8” route covers the mostly flat “greater London” expansion and Box/Fox Hills. It is very similar to the “ Greater London Loop “, only adding ~4km of flat roads and covering the greater London portion in the opposite direction. Route Basics Length: 23.8 km (14.8 miles) Elevation: 276 m (906‘) Lead-In: 0.6 km (0.4 miles) Map: London Restriction: none Achievement Badge: 480 XP London’s “Greater London 8” route covers the mostly flat “greater London” expansion and Box/Fox Hills. It is very similar to the “ Greater London Loop “, only adding ~4km of flat roads and covering the greater London portion in the opposite direction. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks London’s “Greater London Flat” route covers the mostly flat Greater London expansion and most of the Classique route. It is currently the flattest route on the London course. Route Basics Length: 11.7 km (7.3 miles) Elevation: 36 m (118‘) Lead-In: 5.6 km (3.5 miles) Map: London Restriction: none Achievement Badge: 230 XP London’s “Greater London Flat” route covers the mostly flat Greater London expansion and most of the Classique route. It is currently the flattest route on the London course. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks London’s “Greater London Loop” route covers the mostly flat “greater London” expansion and the Box Hill climb. It is essentially the “ London Loop ” with ~6km of flat roads added. Route Basics Length: 21 km (13.0 miles) Elevation: 222 m (728‘) Lead-In: 0.6 km (0.4 miles) Map: London Restriction: none Achievement Badge: 420 XP London’s “Greater London Loop” route covers the mostly flat “greater London” expansion and the Box Hill climb. It is essentially the “ London Loop ” with ~6km of flat roads added. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Greater London Loop Reverse

Animated map provided by ZwiftHacks Route Basics Length: 21.0 km (13.0 miles) Elevation: 255 m (837‘) Lead-In: 0 km ( miles) Map: London Restriction: Event Only Achievement Badge: none See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks London’s “Greatest London Flat” was released with Zwift’s February 1, 2018 update and is the longest “flat” route on the London course. Route Basics Length: 23.6 km (14.7 miles) Elevation: 164 m (538‘) Lead-In: 7.5 km (4.7 miles) Map: London Restriction: none Achievement Badge: 500 XP London’s “Greatest London Flat” was released with Zwift’s February 1, 2018 update and is the longest “flat” route on the London course. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Animated map provided by ZwiftHacks Route Basics Length: 25.6 km (15.9 miles) Elevation: 356 m (1,168‘) Lead-In: 0.6 km (0.4 miles) Map: London Restriction: none Achievement Badge: 510 XP See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

Greatest London Loop Reverse

Animated map provided by ZwiftHacks Simple the reverse version of Greater London Loop , which takes you on the outermost roads of the London map. Route Basics Length: 25.6 km (15.9 miles) Elevation: 318 m (1,043‘) Lead-In: 0.2 km (0.1 miles) Map: London Restriction: Event Only Achievement Badge: none Simple the reverse version of Greater London Loop , which takes you on the outermost roads of the London map. See route detail page, including Strava segments, detailed description, Veloviewer profiles, video ride-thru and more >

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Double Draft Analysis: a Tale of Two Races

Eric Schlange

November 9, 2018

Double Draft Analysis: a Tale of Two Races

Double draft mode is one of the biggest changes we’ve seen in Zwift racing’s recent memory, but it is still being tested by race organizers and used only in a minority of races. (As of November 9th only ~20% of upcoming races are using double draft mode.)

After finishing a ZHR Hare & Hounds race last night I realized it might provide me with the numbers needed to analyze the effects of double draft on racing. You see, I had done the same race a month earlier and put in a very similar effort. But the earlier race was not in double draft mode, while yesterday’s race was. Perfect!

Disclaimers: obviously there is no way to account for each and every variable and make a perfect comparison of two races. While both races were quite similar (similar effort levels, same course, etc) the second race did have more riders in it, which would logically increase the overall speed somewhat. Also, it is worth mentioning that most of this analysis really only applies to the flatter portions of races. Once the road turns uphill drafting matters less, and your watts per kilogram matter more.

First: the Data

Here are some key numbers from the two races.

Draft Type	Normalized Power	Average Power	Average Speed	ZwiftPower Link	Strava Link
Standard	285 watts	278 watts	41.4kph/25.74mph	ZwiftPower	Strava
Double	289 watts	283 watts	43.3kph/26.9mph	ZwiftPower	Strava

I also looked at the numbers of two A racers who rode in both races, and the differences in their numbers match up with my experience in the B’s.

Greg Hagele’s first race was at a normalized power of 289 watts, average power of 287 watts, and a speed of 43.4kph (26.95mph). His second race had a normalized power of 283, average power of 283 watts, and a speed of 44.7kph (27.77mph).
Joseph Noack’s first race was at a normalized power of 262 watts, average power of 256, and a speed of 43.22kph (26.86mph). His second race had a normalized power of 263, average power of 257 watts, and a speed of 44.7kph (27.77mph).

Ride Feel

It is definitely easier to “sit in” while in double draft mode, as the increased draft effect means even more power savings for those drafting. I analyzed Zwift’s draft effect a while back, and while I haven’t done any draft tests in double draft mode, my guess would be that at race speeds, power savings is approximately 35% in double draft mode (compared to 25% without double draft).

I like the feel of double draft more than standard draft, because it’s closer to what I experience outdoors. (Now if we could just be allowed to freewheel a bit without auto-braking…)

Effort

As you can see from the numbers above, my efforts in terms of pure watts haven’t varied much between standard and double draft events. But I will say my perceived effort levels in double draft races have been slightly lower than their standard draft counterparts. I attribute this to three things:

Fewer attacks to chase: racers are learning that it’s hard to pull off a solo breakaway in double draft mode, so you don’t see as many attacks. Those that do happen are rarely followed because the group knows they can catch the break by continuing to push at their current effort level.
Less variability: because of fewer attacks, the group’s overall effort stays more even. My VI for the first race was 1.06, but dropped to 1.03 in the double draft.
Ease of sitting in with the group: with fewer attacks and a stronger draft effect, those who are in the wind continue working at a typical level while those in the draft are holding the wheel with less effort than a standard draft race would require.

It is worth noting that while perceived effort may be slightly lower, the overall group speed is actually higher in double draft races.

Group Speed

This is the most notable effect of double draft: group speed increases. At nearly identical effort levels my speed increased by 1.9kph/1.16mph in the double draft race. The two A riders I looked at showed slightly less difference between races, but still around 1.3kph/.81mph.

My experience also aligns with what I’m hearing from other racers who are saying double draft races are just fast. Recently we’ve seen some A racers get handed the “cone of shame” for going too fast on certain segments in double draft events, and to my knowledge this simply hadn’t happened in standard draft races. Double draft races seem to have brought group speeds to a higher level than we’ve seen before on Zwift.

Are there negative implications to increased group speeds? If you’re a person who likes to solo off the front, yes! The only breaks that will survive with double draft mode will be group breaks which take advantage of the increased draft.

So teamwork looks like the key to winning double draft races from a breakaway. If you’re not the breakaway type, your results will come down to the ability to hang in then unleash a killer sprint for the line.

What about you? Are you a veteran Zwift racer who has tried some double draft events?

I’d love to hear how your experience compares to mine. Please share below!