Nine powerboats left Tower Bridge on Saturday morning for the start of the Venture Cup Prologue.
The main Venture Cup race from Tower Bridge to Monte Carlo will take place in summer 2014.
This week's prologue event will see nine competitors race from Tower Bridge to the Channel Islands before returning across the channel to Bournemouth and Poole.
A week ago Tower Bridge was the start point for the GB Row Challenge around the coast of Great Britain. Only two of the boats which left Tower Bridge remain in contention for the £100,000 bounty.
• Photographs courtesy of Peter Harding.