Cheer on Team GB triathletes this weekend as the World Triathlon Grand Final plays out on the streets of central London.
As at last summer's Olympics, the swimming gets swum in the Serpentine, then it's a cycle around Hyde Park and Buckingham Palace followed by a gruelling run back in the park (course map).
In all, there are five days of swimming, cycling and running action. On Wednesday 11 September Aquathlon (two stage swimming and running) races take place across age groups. Thursday 12 September sees the Juniors and U23 triathletes compete. On Friday 13 September it's the Paratriathlon, then it's the turn of the Elite Women on Saturday and the Elite Men on Sunday, with non-elite age group races slotted around them.
The men's race, has particular home-team interest with British brothers Jonny (World Champion) and Alistair (Olympic Gold Medallist) Brownlee vying for glory.
All of this is free to watch in Hyde Park and on the streets. Download a free spectator guide to make the most of your sporting day out.
In addition, throughout the five days, Trafalgar Square becomes Triathlon Square and a place to watch the races on the big screens with plenty of opportunities to have a go, in the Endless Pool (basically, a watery version of a treadmill), on Static Bikes and Treadmills . Test your triathlon mettle!
Olympic Triathlon photo by Darren Johnson via Londonist Flickrpool.