Two London Triathlons takes place within two weeks of each other this summer.
This weekend, 30-31 July, Virgin Active run their London Triathlon out of the ExCel Arena Docklands. It's the world's biggest triathlon and open to all. Over 13,000 competitors are expected to compete over three different distances: Supersprint, Sprint and Olympic (1500 metre swim, 40km bike and 10km run).
Swimming is outdoors in Royal Victoria Docks. Jensen Button is a regular and other slebs include Sporty Spice and Stacey Solomon.
A week later the Dextro Energy Triathlon London will be held in Hyde Park and around Buckingham Palace over the weekend of 6-7 August. Part of the World Championship Series this is an Olympic test event.
World class elite athletes will run the Olympic course whilst some of the 4,500 amateur triathletes - divided into age groups - will be able to compete on part of it too with swimming in the Serpentine. This event also hosts the world's only elite Paratriathlon - not at this stage an Olympic discipline.
If you didn't get tickets for 2012 action, get to Hyde Park and watch this. Both events are free to spectate and the latter will be televised by the BBC.
Check back with us next Monday for the lowdown on Olympic Triathlon.