Orobus | Action Medical Research

The UK’s Toughest
One-Day Ultra Ride

London - Bath - London
400km Ultra Ride

2018 date coming soon


The Orobus is our epic Orobus cycling challenge; a mammoth 400km ride from London to Bath and back again. Taking riders on some of the oldest roads in the country, through historic countryside and with stunning views it is a truly special challenge.

In Greek mythology the Ouroboros was a self-devouring serpent. Taking inspiration from the legend we designed our Orobus ride to test riders to the limit and offer one of the hardest single day UK rides. Setting off from London in the early hours riders will make their way through 7 counties with over 10,000 ft of climbing and some spectacular roads. Roads from London to Bath have existed since Roman times and the route is steeped in historical significance and history.

To help riders tackle this immense challenge the route will be fully signed, with plenty of well stocked feed stations, moto marshals, mechanical and medical support and hot food at the finish.

Orobus Lite

For those not daring enough to tackle the full 400km challenge there will be a one way lite option from London to Bath. Setting off from London riders will tackle the northern route of the Orobus riding 116 miles to the finish in Bath. Lite riders will have to make their own way back from Bath.

Key Information

Distance: 246 miles / 117 miles
Start: King's House Sports Ground, Riverside Drive, Chiswick, London, W4 2SH
Start Time: 05:00 am – Finish Time 22:00
Orobus Self Payment: £200
Orobus Fundraising Option: £50 registration + £300 fundraising
Orobus Lite: £50


Get your cycling jersey

Action Medical Research cycling jersey



Join our fight for little lives


There are hundreds of thousands of children in the UK whose lives are devastated by disease and disability. It’s too many. Far too many. Research can put a stop to this.

For more than 60 years Action Medical Research has helped pioneer treatments and ways to prevent disease that have benefited millions of people in the UK and across the world. Our research has helped to beat polio in the UK, develop ultrasound in pregnancy, fight meningitis and prevent stillbirths.

But we urgently need to develop more new treatments and cures for sick babies and children and we can’t do it without you.


What's included

  • Fully Signed Route
  • Online Mapping support and GPX files
  • Training support and advice
  • Well stocked food stops
  • Finishers Medal
  • Hot food at the finish
  • Roaming mechanics
  • Broom Wagon
  • Bag drop


We recommend that you have cover for you and your bike
Yes, for most common bikes. Spares are chargeable
On the day you will be given a contact number for our ride control, who will help with any issues
There are several cut off points along the ride. All riders on the Orobus event must have reached the halfway point in Bath by 13:30 to continue on the ride. Any riders arriving after this time will be offered return bike and rider transport from Bath. The official cut off time for riders returning to London is 22:00 giving riders 16 hours and 30 minutes to complete the ride
You must wear a cycle helmet to take part
You must be at least 16 on the day of the event to take part; if you are under 18 you must be accompanied by an adult
There will be basic changing facilities at the start and finish and most of our checkpoints will have toilet facilities. Your belongings/valuables should be locked in your car or carried with you. There are well stocked feed stations along the route. Hot food and drinks will be provided for all Orobus finishers
Front and rear lights are compulsory for all riders taking part in the Orobus ride
Registration: 05:00-05:30 for Orobus riders and from 06:30-07:30 for Lite riders
Start: 05:30 – 05:45 for Orobus riders and 07:00-07:30 for Lite riders
Cut off Times: There is a 14:00 cut off time at Bath for Orobus riders and the event finish time is 21:30
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