100K ultra runs

100K ultra runs

The UK's most comprehensive calendar of 100K ultra runs - a serious endurance challenge at over 60 miles and taking a full day to complete! Search by date, location or map to find a 100K ultra marathon near you or browse to discover your perfect event.

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100K ultra runs in the UK

The middle of the common ultra distances at just over 60 miles, 100K ultra marathons are a big step up from the marathon. Despite this, distance is not always the key challenge with ultra runs - the total ascent gives a much better indication of how hard it will be. Select your location to find 100K ultra runs in your area or scroll down to browse events coming up.

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100K ultra runs in 2024/2025

Featured events are listed below - select a month/region or the map view to see all events.

This event gives participants the opportunity to take in a runnable, beautiful route which follows the North Walian coastline between Prestatyn and Bangor.
  • Sat 26 Apr 2025
  • £84.50
Prestatyn, Clwyd, UK

North Wales 50K & 100K | 100K

This event gives participants the opportunity to take in a runnable, beautiful route which follows the North Walian coastline between Prestatyn and Bangor.

  • 100 km trail running
An epic challenge, making a full 106km circuit of the Isle of Wight, starting and finishing in Chale, enjoy well stocked rest stops and superb scenery every step of the way.
  • Sat 3 May 2025
  • £199
Ventnor, Isle of Wight, UK

Isle of Wight Ultra Challenge | Full continuous

An epic challenge, making a full 106km circuit of the Isle of Wight, starting and finishing in Chale, enjoy well stocked rest stops and superb scenery every step of the way.

  • 106 km multi terrain running + 1960 m ascent
The full 106km circumnavigation of the Isle of Wight, in daylight hours. Overnight at Cowes for a well-earned rest on this wonderful exploration of the coastal routes around the island.
  • Sat 3 - Sun 4 May 2025
  • £199
Ventnor, Isle of Wight, UK

Isle of Wight Ultra Challenge | Full 2 day daylight

The full 106km circumnavigation of the Isle of Wight, in daylight hours. Overnight at Cowes for a well-earned rest on this wonderful exploration of the coastal routes around the island.

  • 106 km multi terrain running + 1960 m ascent
A demanding challenge, taking on 100km along the UNESCO World Heritage Jurassic Coast, starting from Corfe Castle on a fully-supported challenge visiting the highlights of the region.
  • Sat 17 - Sun 18 May 2025
  • £199
Wareham, Dorset, UK

Jurassic Coast Ultra Challenge | Full 100km continuous

A demanding challenge, taking on 100km along the UNESCO World Heritage Jurassic Coast, starting from Corfe Castle on a fully-supported challenge visiting the highlights of the region.

  • 100 km trail running + 2300 m ascent
Take on the full 100km challenge across two days, to enjoy the entirety of the route during daylight, with camping options at the halfway Basecamp in Weymouth.
  • Sat 17 - Sun 18 May 2025
  • £199
Wareham, Dorset, UK

Jurassic Coast Ultra Challenge | Full 100km over 2 days

Take on the full 100km challenge across two days, to enjoy the entirety of the route during daylight, with camping options at the halfway Basecamp in Weymouth.

  • 100 km trail running + 2300 m ascent
Walk, jog or run the journey from Capital to Coast, over the North and South Downs. A fully supported challenge leaving Richmond-upon-Thames for the finish line at Brighton Racecourse.
  • Sat 24 May 2025
  • £199
Richmond, UK

London 2 Brighton Ultra Challenge | Full 100km continuous

Walk, jog or run the journey from Capital to Coast, over the North and South Downs. A fully supported challenge leaving Richmond-upon-Thames for the finish line at Brighton Racecourse.

  • 100 km trail running + 1500 m ascent
Walk, jog or run the full 100km London to Brighton route, over two daytime sessions, with an overnight stop at the Basecamp at Turners Hill.
  • Sat 24 - Sun 25 May 2025
  • £199
Richmond, UK

London 2 Brighton Ultra Challenge | Full 100km over 2 days

Walk, jog or run the full 100km London to Brighton route, over two daytime sessions, with an overnight stop at the Basecamp at Turners Hill.

  • 100 km trail running + 1500 m ascent
Take on the full 100km challenge, starting from Kendal Base Camp, a fully supported ultra. making a glorious loop of the spectacular south Lakes.
  • Sun 1 - Sun 8 Jun 2025
  • £199
Kendal, Cumbria, UK

Lake District Ultra Challenge | Full 100km continuous

Take on the full 100km challenge, starting from Kendal Base Camp, a fully supported ultra. making a glorious loop of the spectacular south Lakes.

  • 100 km trail running + 2500 m ascent
Take on the full 100km challenge during the hours of daylight, split over the two days. Enjoy the whole incredible route, whilst also getting a well-deserved overnight sleep.
  • Sat 7 - Sun 8 Jun 2025
  • £199
Kendal, Cumbria, UK

Lake District Ultra Challenge | Full 100km over 2 days

Take on the full 100km challenge during the hours of daylight, split over the two days. Enjoy the whole incredible route, whilst also getting a well-deserved overnight sleep.

  • 100 km trail running + 2500 m ascent
Take on a 100km challenge, making a fully supported loop from Cirencester, exploring the picturesque, undulating terrain of the Cotswolds on a spectacular challenge.
  • Sat 21 - Sun 22 Jun 2025
  • £199
Cirencester, Gloucestershire, UK

Cotswold Way Ultra Challenge | Full 100km continuous

Take on a 100km challenge, making a fully supported loop from Cirencester, exploring the picturesque, undulating terrain of the Cotswolds on a spectacular challenge.

  • 100 km trail running + 2250 m ascent
Walk, jog or run the full 100km challenge, split over two days, with a well deserved nights sleep at the half way basecamp, to recharge your batteries overnight.
  • Sat 21 - Sun 22 Jun 2025
  • £199
Cirencester, Gloucestershire, UK

Cotswold Way Ultra Challenge | Full 100km over 2 days

Walk, jog or run the full 100km challenge, split over two days, with a well deserved nights sleep at the half way basecamp, to recharge your batteries overnight.

  • 100 km trail running + 2250 m ascent
Take on the full 100K Race to the King ultra marathon challenge in one go. Fully supported through day and night on a route combining castles and coastal scenery.
  • Sat 21 - Sun 22 Jun 2025
  • £160
Chichester, West Sussex, UK

Race to the King | 100K Non-stop

Take on the full 100K Race to the King ultra marathon challenge in one go. Fully supported through day and night on a route combining castles and coastal scenery.

  • 100 km trail running + 4619 ft ascent
Take on a 100km challenge, starting and finishing at the Bakewell Showground on a fully supported exploration of the beautiful Peak District National Park.
  • Sat 28 - Sun 29 Jun 2025
  • £199
Bakewell, Derbyshire, UK

Peak District Ultra Challenge | Full 100km continuous

Take on a 100km challenge, starting and finishing at the Bakewell Showground on a fully supported exploration of the beautiful Peak District National Park.

  • 100 km trail running + 2150 m ascent
Undertake the full 100km challenge, split over two days, to allow a good nights rest and appreciate the glorious scenery during the daytime.
  • Sat 28 - Sun 29 Jun 2025
  • £199
Bakewell, Derbyshire, UK

Peak District Ultra Challenge | Full 100km over 2 days

Undertake the full 100km challenge, split over two days, to allow a good nights rest and appreciate the glorious scenery during the daytime.

  • 100 km trail running + 2150 m ascent
Take on the full 100K Race to the Stones ultramarathon in one go. Fully supported through day and night on an incredibly scenic and historic route.
  • Sat 12 Jul 2025
  • £50
Watlington, Oxfordshire, UK

Race to the Stones | 100K Non-stop

Take on the full 100K Race to the Stones ultramarathon in one go. Fully supported through day and night on an incredibly scenic and historic route.

  • 100 km trail running + 3704 ft ascent
Take on the full 100K Race to the Stones ultramarathon with an overnight stop at the all-inclusive Basecamp, meaning a good nights' sleep in between the 50K stints.
  • Sat 12 Jul 2025
  • £250
Watlington, Oxfordshire, UK

Race to the Stones | 100K Two Days with camping

Take on the full 100K Race to the Stones ultramarathon with an overnight stop at the all-inclusive Basecamp, meaning a good nights' sleep in between the 50K stints.

  • 100 km trail running + 3704 ft ascent
Take on the full Race to the Stones 100K ultramarathon over two days, making your own arrangements for overnight accommodation at the halfway point.
  • Sat 12 Jul 2025
  • £160
Watlington, Oxfordshire, UK

Race to the Stones | 100K Two Days no camping

Take on the full Race to the Stones 100K ultramarathon over two days, making your own arrangements for overnight accommodation at the halfway point.

  • 100 km trail running + 3704 ft ascent
Yr Wyddfa (Snowdon) is the highest mountain in England and Wales. Your challenge is to ascend and descend as many times as possible in 24 hours - solo or as a relay team.
  • Sat 12 - Sun 13 Jul 2025
  • £121.99-£251.99
Caernarfon, Gwynedd, UK

Black Diamond Yr Wyddfa Snowdon24

Yr Wyddfa (Snowdon) is the highest mountain in England and Wales. Your challenge is to ascend and descend as many times as possible in 24 hours - solo or as a relay team.

  • 24 hrs trail running
The full distance option of the South Coast Challenge from sunny Eastbourne, over the magnificent Seven Sisters, onto Cuckmere Haven and over the South Downs all the way to historic Arundel.
  • Sat 6 - Sun 7 Sep 2025
  • £199
Polegate, East Sussex, UK

South Coast Ultra Challenge | Full 100km continuous

The full distance option of the South Coast Challenge from sunny Eastbourne, over the magnificent Seven Sisters, onto Cuckmere Haven and over the South Downs all the way to historic Arundel.

  • 100 km trail running + 2100 m ascent
The full distance option of the South Coast Challenge over 2 days with 57km on day 1 and 43km on day 2, meaning you experience the route in daylight with the chance to sleep overnight.
  • Sat 6 - Sun 7 Sep 2025
  • £199
Polegate, East Sussex, UK

South Coast Ultra Challenge | Full 100km over 2 days

The full distance option of the South Coast Challenge over 2 days with 57km on day 1 and 43km on day 2, meaning you experience the route in daylight with the chance to sleep overnight.

  • 100 km trail running + 2100 m ascent
The full, non-stop option of the Thames Path Challenge from leafy South West London following the river to Hampton Court, Runnymede to finish at Henley-on-Thames for a celebratory finish and BBQ.
  • Sat 13 - Sun 14 Sep 2025
  • £199
London, UK

Thames Path Challenge | Full 100km continuous

The full, non-stop option of the Thames Path Challenge from leafy South West London following the river to Hampton Court, Runnymede to finish at Henley-on-Thames for a celebratory finish and BBQ.

  • 100 km trail running + 350 m ascent
The full distance option of the Thames Path Challenge over 2 days with 50km on day 1 and 50km on day 2, meaning you experience the route in daylight with the chance to sleep overnight.
  • Sat 13 - Sun 14 Sep 2025
  • £199
London, UK

Thames Path Challenge | Full 100km over 2 days

The full distance option of the Thames Path Challenge over 2 days with 50km on day 1 and 50km on day 2, meaning you experience the route in daylight with the chance to sleep overnight.

  • 100 km trail running + 350 m ascent
  • Sat 7 Jun 2025
  • £109
Castle Douglas, Dumfries and Galloway, UK

Ultra Scotland 50

Take on 50 historic miles across the beautiful Southern Upland Way - one of the greatest trails in the UK. Ultrarunners will tackle several ascents, pass through forests, valleys and by lochs.

  • 56 miles trail running + 2447 m ascent

100K ultra runs near you

Select your location for 100K ultra marathons in your area.