What's this? It looks like a very short inside out lock, which in a way is what it is. The V gates in a lock always point to the higher water. Well in this case, that could be either side because to the right the level might be high of low according to the tide. Let's look at the bigger picture.
Now you can see we have a normal lock in the background, with an extra pair of outward pointing tidal gates at this end.
Where is it?
Literally a stone throw from the Olympic Stadium. It is City Mill lock on the Bow back rivers, linking the City Mill river with the tidal Waterworks River which goes on to flow past the stadium. We came upon it when we were there last week.