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Flat 50K ultra runs in South East in December 2025

Find flat 50k 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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Come and join the day of running and aim to complete an ultra marathon at your own pace on a flat, out-and-back route along the River Thames then receive a bespoke medal and goody bag at the finish!
  • Fri 26 Dec
  • £33-£35
Egham, Surrey, UK

Boxing Day Challenge | Ultra Marathon

Come and join the day of running and aim to complete an ultra marathon at your own pace on a flat, out-and-back route along the River Thames then receive a bespoke medal and goody bag at the finish!

  • Enter online
  • Flat
  • Traffic free
  • Age 20 & over
  • 32 miles trail running
  • Sun 21 Dec
Southsea, Hampshire, UK

Portsmouth Coastal Waterside Marathon Events | 50K Ultra

  • 50 km multi terrain running

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