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Flat Ultra runs in South East in December 2025

Find flat ultra runs in South East in December 2025 - filter by date, location or category, display on a map or use the advanced search to find your perfect race.

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Welcome to the 6-hour Boxing Day Challenge, where you can run the distance of your choice on an out-and-back route along the River Thames, with fuel stations, bespoke medal and goody bag.
  • Fri 26 Dec
  • £16-£35
Egham, Surrey, UK

Boxing Day Challenge

Welcome to the 6-hour Boxing Day Challenge, where you can run the distance of your choice on an out-and-back route along the River Thames, with fuel stations, bespoke medal and goody bag.

  • Families
  • Beginner-friendly
  • Event village
  • Age 12 & over
  • 5K run
  • 10K run
  • Half marathon
  • Marathon
  • Ultra run
  • + 1 more race
  • Sun 21 Dec
Southsea, Hampshire, UK

Portsmouth Coastal Waterside Marathon Events | 50K Ultra

  • 50 km multi terrain running

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