⏵ Course guide · Northwest Connecticut road ultra
The Jack Bristol Lake Waramaug Ultra Races loop rolling, mostly flat paved roads around Lake Waramaug in Kent, Connecticut, over 100K, 50 Mile, or 50K, and carry real history as the oldest ultras in Connecticut and the oldest 100K in the United States. I will walk you through the course and lap structure first, then give you a pacing and fueling plan built for a road ultra. There are free calculators along the way to dial in your own numbers.
These facts come from the official UltraSignup event page. Entry fees and any updates are best confirmed there or through the race's Facebook group before you register.
Every distance shares the same road surface and the same opening move: a clockwise 2.2 mile out from the start, then a counter-clockwise return, before settling into repeated laps.
The 50K covers three 7.6 mile laps around the lake, plus a 1.9 mile out-and-back to complete the distance. That lap structure means you pass the start/finish and its aid support regularly, keeping logistics simple even on a road ultra of this length.
The 50 Mile runs six complete laps of the same lake loop, no separate out-and-back segment needed to hit the distance. Consistency across six laps, rather than a fast start, is what separates a strong finish from a fade here.
The 100K covers seven laps plus a 2.3 mile out-and-back to close out the distance, the longest day on offer at just over 62 miles. With a 13 hour cutoff, pacing the early laps conservatively matters more here than in the shorter distances, since there is real time to make up on the closing miles if the early laps are managed well.
Rolling paved roads reward a steady, even effort across every lap far more than an aggressive first-lap split, especially at 50 Mile and 100K length.
Since every distance repeats the same lap, your first lap split is the best predictor you will get of what you can actually sustain. Treat it as a calibration lap rather than a statement, then aim to hold within a narrow band of that pace across the remaining laps. Use a race-time prediction built from your recent training to set a realistic target before race day.
For the 50 Mile and especially the 100K, a recent long race gives you an honest read on what pace holds up across that many hours on your feet, road surface or not. Use it to set a target that survives seven laps, not just three.
⏵ Free tools to plan your effort
Four aid stations spaced roughly every couple of miles around the lake give you frequent resupply, so your fueling plan can lean on the course rather than carrying everything yourself.
With aid roughly every 1.7 to 2.2 miles, you have a real opportunity to fuel little and often rather than carrying a heavy load. Aim for roughly 60 to 90 grams of carbohydrate per hour once you are several hours in, and use the predictable spacing to build a consistent per-lap fueling routine rather than improvising.
Late April in northwest Connecticut can run cool at a 6:30 or 7:30 AM start and warm up meaningfully by afternoon, especially for 50 Mile and 100K runners still out several hours later. Layer accordingly at the start and adjust your fluid and sodium plan as the day warms.
⏵ Build your fueling plan
Get a carb, sodium, fluid, and caffeine plan per hour built for your weight and your chosen distance with the free ultra fueling calculator. Browse the rest of the free running tools at the tools hub.
⏵ Train for it with Summit Line
Get a training plan built around YOUR fitness and this exact rolling road-ultra profile. Summit Line reads your real training, builds a plan for an honest lap-by-lap effort, and helps you dial in race-day pacing so race day is something you execute, not guess at.
It is a set of three ultra distances, 100K, 50 Mile, and 50K, run on rolling paved roads that loop around Lake Waramaug in Kent, Connecticut. It carries real history behind it: the race bills itself as the oldest ultras in Connecticut and the oldest 100K in the United States, with the 2027 edition marking its 53rd anniversary.
This is a road ultra on rolling but primarily flat paved roads, not singletrack trail. Every runner starts with the same clockwise 2.2 mile out and counter-clockwise return, then settles into repeated laps around the lake: three 7.6 mile laps plus a 1.9 mile out-and-back for the 50K, six laps for the 50 Mile, and seven laps plus a 2.3 mile out-and-back to finish for the 100K.
The road surface and rolling-but-mostly-flat profile make this considerably more approachable than a technical trail ultra of the same distance, so the main challenge is sustaining pace over repeated laps rather than fighting difficult terrain. The 100K in particular is still a long day given its 62 mile distance and seven laps, and the 13 hour cutoff means you do need a real pacing plan, not just fitness.
The 50K carries a 12 hour cutoff, while both the 50 Mile and 100K carry a 13 hour cutoff. Given the road surface and rolling-but-flat terrain, those windows are generous compared to a trail ultra of the same distance, but still worth building a real pace plan around, especially for the 100K.
The paved, rolling-but-mostly-flat course and four well-stocked aid stations spaced roughly every couple of miles make this a genuinely approachable first ultra, especially if your background is road or track running rather than technical trail. The repeated-lap format also means you pass familiar ground and support regularly, which helps first-timers manage the mental side of a long distance.
The race is billed as the oldest ultras in Connecticut and the oldest 100K in the United States, with the 2027 running marking its 53rd anniversary, a lineage stretching back roughly five decades. That history is part of what draws repeat entrants and gives the event a strong community feel around Lake Waramaug every spring.
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<a href="https://runsummitline.com/guides/jack-bristol-lake-waramaug-ultra-races">The Jack Bristol Lake Waramaug Ultra Races course guide</a><iframe src="https://runsummitline.com/embed/race/jack-bristol-lake-waramaug-ultra-races" style="width:100%;max-width:420px;height:180px;border:0;" loading="lazy" title="Jack Bristol Lake Waramaug Ultra Races course guide by Summit Line"></iframe>This guide is independent and for planning only. The course details and dates come from public sources and can change year to year, so confirm the current specifics with the official race before you register or run. The pacing and fueling advice is general and not medical advice.
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