A 161 km (100 mile) point-to-point ultramarathon from Richmond in London to Oxford following the Thames Path National Trail, with approximately 560 m of ascent. The route tracks the River Thames upstream on largely flat terrain including towpaths, parkland paths and sections of compact trail and pavement. Elevation gain is minimal and accumulated gradually. Underfoot surfaces are predominantly firm and consistent, making the challenge primarily distance-based rather than terrain-driven. The course is fully marked with numerous aid stations positioned along the route in line with Centurion Running event structure.