Thames Ring Series

The Thames Ring Series is a legendary ultra-distance running challenge that follows rivers and canals on a tough loop through countryside and historic towns, with 100-mile, 150-mile and 250-mile options.

Dates: Wed 22 Apr 2026 to Sun 26 Apr 2026 (event weekend). Individual race start times vary.

The Thames Ring Series is one of the UK’s toughest ultra-distance challenges, taking runners along scenic riverside and canal paths through several counties. The event features multiple distance options designed to test endurance, navigation and resilience within strict cut-offs.

Races and start times

• TR150 (150 miles trail running) – Wed 22 Apr 2026 at 10.00am – £175
• TR250 (250 miles trail running + 2857 ft ascent) – Wed 22 Apr 2026 at 10.00am – £350
• TR100 (100 miles trail running) – Fri 24 Apr 2026 at 12.00pm – £125

Highlights

• 250-mile circular route through several counties
• 100-hour time limit for the full course
• Riverside and canal scenery
• Checkpoints with food and drink, plus dropbag transfers
• Additional 100-mile and 150-mile options

Key event information

• Age: 18+ (all races)
• Support rules: no outside support except limited assistance at specific checkpoints; runners are expected to be self-sufficient for food and kit
• Pacers: not permitted
• Compulsory kit: a kit list will be provided by the organiser

Event HQ: Morrell Rooms, Church Lane, High Street, Streatley, Reading, Berkshire, RG8 9JA, UK.