Compiled and fact-checked by Tommo, Verus founder · Last verified August 2026 · Spot an error?

Running · Ultra Marathons

Thames Ring 250 2027

Race day
Wednesday, 21 April 2027
Location
Streatley, Berkshire — a loop of the Thames and the canals, UK
Distance
250 mi / 402.3 km

Thames Ring 250: 21 April 2027, 250 miles, from Streatley, Berkshire. Entry, route, a pace chart and the race-day forecast.

223Days

Thames Ring 250 Race Timeline

Training Phase Build Phase Taper Race Week Race Day Race Completed

223 days to go

More than 126 days out — a good window to build a consistent base before ultra-specific training ramps up.

Generated mark — no elevation published for this course

Thames Ring 250 2027: quick answers

When is Thames Ring 250 2027?

Thames Ring 250 2027 takes place on Wednesday, 21 April 2027, starting at The 250 starts on Wednesday 21 April 2027.

What time does Thames Ring 250 start?

Thames Ring 250 starts at The 250 starts on Wednesday 21 April 2027 from Streatley, Berkshire.

Where does Thames Ring 250 start and finish?

Thames Ring 250 starts at Streatley, Berkshire and finishes at Streatley, Berkshire.

How many miles is Thames Ring 250?

Thames Ring 250 is 250 miles (402.3km).

How much does Thames Ring 250 cost to enter?

Entry through Eventrac, closing on 1 April 2027. A 100-mile version starts at midday on the Friday with a 34-hour cut-off.

Key Race Metrics & Overview

Date
Wednesday, 21 April 2027
Distance
250 miles / 402.3km
Location
Streatley, Berkshire — a loop of the Thames and the canals, UK
Start Point
Streatley, Berkshire
Finish Point
Streatley, Berkshire
Start time
The 250 starts on Wednesday 21 April 2027
Surface
Thames Path and canal towpath throughout — flat, hard-packed and continuous
Cut-off time
100 hours for the 250 mile. The 100-mile version has 34 hours, from midday Friday to 22:00 Saturday.

Not published by the organiser at the time of writing: age requirement, tracking app. Verus records these as unconfirmed rather than estimating them — check the official race website closer to race day.

Direct Entry Summary

Entry through Eventrac, closing on 1 April 2027. A 100-mile version starts at midday on the Friday with a 34-hour cut-off.

Ballot Policy

No ballot — entry is direct through Challenge Running.

Thames Ring 250 Race Day Weather

A real forecast appears here once one exists for race day — usually about a week to ten days out. Nothing is shown until then, because a made-up forecast is worse than none.

Thames Ring 250 Route Map & Elevation Profile

Starting at Streatley, Berkshire and finishing at Streatley, Berkshire. Total elevation gain is not published for this event, and Verus does not estimate one.

Is Thames Ring 250 flat?

No official elevation figure is published for this course, so Verus doesn't state one. The organiser describes the going as: thames path and canal towpath throughout — flat, hard-packed and continuous.

Thames Ring 250 Course Profile

Elevation change not published for this event.

Startmi 125.0250mi

Tap a point on the course for details.

mi 0.0

Streatley, Berkshire

Start line.

Where Thames Ring 250 starts and finishes

Thames Ring 250 starts at Streatley, Berkshire and finishes at Streatley, Berkshire. We haven't been able to place those on a map accurately enough to show one — a pin in the wrong place is worse than no pin.

These are the start and finish points, not the route. Verus doesn't hold course files for this race, and drawing a line between two pins would be a guess you might end up training on.

Full Thames Ring 250 Route Breakdown

A 250-mile loop of the Thames and the canal network from Streatley, run over 21-25 April 2027 with a 100-hour limit. Almost entirely on towpath — the Thames Path out, the Oxford and Grand Union canals round, and the Thames back. One of the longest single-stage races in Britain.

Thames Ring 250 Pace Calculator & Splits

Thames Ring 250 Pace Calculator

Enter a target finish time to see your pace and projected splits.

hrs
min
sec
target time

Average pace / mile

0:58

Average pace / km

0:36

5K2:59
10K5:58
Half Marathon12:35
30K17:54
Finish4:00:00

Thames Ring 250 Pace Chart

Split markers calculated for standard checkpoints — no official pacers are confirmed for this event.

Target Pace /mi Pace /km 5K10KHalf Marathon30KFinish
3:00 0:43 0:27 2:144:289:2613:253:00:00
3:15 0:47 0:29 2:254:5110:1414:323:15:00
3:30 0:50 0:31 2:375:1311:0115:403:30:00
3:45 0:54 0:34 2:485:3611:4816:473:45:00
4:00 0:58 0:36 2:595:5812:3517:544:00:00
4:15 1:01 0:38 3:106:2013:2219:014:15:00
4:30 1:05 0:40 3:216:4314:0920:084:30:00
4:45 1:08 0:43 3:337:0514:5721:154:45:00
5:00 1:12 0:45 3:447:2715:4422:225:00:00
5:30 1:19 0:49 4:068:1217:1824:365:30:00
6:00 1:26 0:54 4:288:5718:5326:516:00:00
6:30 1:34 0:58 4:519:4220:2729:056:30:00
7:00 1:41 1:03 5:1310:2622:0131:197:00:00

Thames Ring 250 Finish Time Estimator

Enter a recent 5K, 10K or Half Marathon time to estimate your Thames Ring 250 finish time.

Your 5K time

hrs
min
sec

Estimated Thames Ring 250 finish

43:37:33

An estimate only, based on Pete Riegel's race-time prediction formula. Real marathon performance depends on endurance, training specificity, pacing and race-day conditions — not just your speed over a shorter distance.

Training for a different distance? Try the full pace calculator, race time predictor or pace chart.

Got your target time? Save it to your profile.

Tag Thames Ring 250, set your goal pace, and let Verus track your countdown, training and fundraising in one place.

Start Your Verus Journey

Thames Ring 250 Race Day Checklist

Tap items to mark off your race-day readiness.

0/4
  • Race number attached, and any timing chip fitted per your race pack instructions
  • Weather-appropriate kit, plus something warm and disposable to discard before the start
  • A plan for reaching Streatley, Berkshire
  • A meeting point agreed with family and friends for after the race

Training Strategy for Thames Ring 250

Standard Training Window

20-24 weeks is the realistic window for a first 250-mile ultra, assuming you already have a marathon's worth of base behind you. The block that matters is back-to-back long weekends — a long run on Saturday followed by a second, slower one on Sunday — which builds time on feet and teaches you to run on tired legs without the recovery cost of one enormous day. Practise your race-day nutrition on every one of them; at this distance the stomach fails before the legs do.

Terrain Specificity

This is a largely flat course, so most of your long runs can mirror that — flat and steady, building time on feet rather than hill strength.

The Taper Phase

Drop volume hard across the final three to four weeks — further out and steeper than a marathon taper, because a 30-mile training day costs weeks of recovery, not days. Keep some easy running and a little terrain-specific work in, but the goal is to reach Streatley, Berkshire with fresh feet and a rested gut rather than one more long run in the bank.

Pacing Execution

Lock in your target pace using the interactive splits calculator below — no official pacers are confirmed for this event, so a pace band on your watch is the more reliable option.

Fuel & Hydration Prep

Test your race-day fuel and hydration plan on your long training runs, not for the first time on race day — check the Race Day Checklist below for what's actually on this course.

250-Mile Ultra Nutrition & Fueling Plan

2-3 Days Prior

A deliberate increase in carbohydrate over the two to three days before the race is the well-established approach at marathon distance.

Race Morning

Eat a carbohydrate-focused breakfast two to three hours before the start, and stick to something you've already tested in training rather than trying anything new.

On-Course Fueling

Most runners take on carbohydrate every 30 to 45 minutes from about an hour in, alongside fluid at the on-course stations.

Post-Race Recovery

A mix of carbohydrate and protein in the hour or so after finishing supports recovery.

Thames Ring 250 Charity Places 2027

No formal charity-place scheme published — runners commonly fundraise for a charity of their own choosing.

Impactful Storytelling

Lead with your personal story — explain why the charity matters to you. Personal connection generates 3x more support than a generic link broadcast.

Social Campaign Milestones

Share key training milestones on Instagram (first 10-miler, peak week, race week) with your fundraising link in bio. Publicly thanking donors prompts secondary gifts!

Running Thames Ring 250 for charity?

Link your JustGiving page to Verus and show up right here alongside other Thames Ring 250 fundraisers — goal, progress and story, all in one place.

Add Your Fundraiser to Verus

Travel & Logistics

Road closures

No road closures — the Thames Ring 250 is run off-road (Thames Path and canal towpath throughout — flat, hard-packed and continuous), so local traffic is unaffected.

Thames Ring 250 Frequently Asked Questions

Everything you need to know for race weekend.

Race details independently compiled and fact-checked by Tommo against the official Thames Ring 250 site , last verified August 2026. Always confirm official timings and policies directly prior to race day.