The River Thames Half Marathon starts at 8:30am from Cowey Sale by Walton Bridge, running 13.1 miles along road, path and the Thames towpath towards Hampton Court Bridge and back. The organisers describe the course as flat, fast, scenic and largely traffic free.
Entry is online in advance through River Thames Running. No finish time is published for the event.
Source: River Thames Running. Always verify details directly with the organiser before attending.