The world's biggest triathlon is expected to attract 13,000 competitors and 30,000 spectators - so make sure you know the best place to get a good view of all the action.
The event, at the Excel centre in Newham's Royal Victoria Dock will be held on Saturday, August 8, and Sunday August 9.
Here is where to watch the various disciplines:
You can watch those swimming in the Royal Victoria Dock from all around the dockside, which you can get to from either side of the Excel centre. There will also be a bridge the the east of the Excel centre where people can stand.
The recommended place to watch is from the west entrance of the Excel centre (before the multi storey car park). Both the walkways from the DLR at Custom House Station and Prince Regent Station to ExceL or from under the Fox pub at ground level are also great viewing points.
In Canary Wharf South Colonnade will be a good place to catch the Sunday cycle route. It will not pass through here on Saturday.
Head to the east of the Excel centre for a view of the runners as the route stretches along the north edge of the dock. The run route also loops through the expo so you can watch from inside as well.