[2] Across the weir pool is a large Environment Agency complex which monitors the River Thames, while a small office building exists on the front lawn opposite from the lock house.
The weir is upstream of the lock alongside the navigation channel in two parts and feeds the Osney pool.
The lock can be reached a short way down the towpath from Osney Bridge on the A420 Botley Road on the way west out of the centre of Oxford.
On the other side of the island is Castle Mill Stream, an old navigation channel that runs to the east closer to the centre of Oxford rejoining the Thames below the lock.
There are navigation transit markers alongside Port Meadow upstream of Medley Boat station, to allow river users to check their speed.