It is in open country to the north of Oxford, Oxfordshire, on the southern bank of the river.

Behind the island is the start of the Wolvercote Mill Stream leading to Dukes Cut, which connects the Thames to the Oxford Canal.

The weir had a history of complaints about the water level and lack of attendance for the flash lock.

The lock can be reached down a long track leading from the Godstow road just where it passes under the A34 Oxford by-pass.

Above the lock is the connection with Dukes Cut on the northern side and further on, on the southern bank, the Seacourt Stream separates off to rejoin at Kennington Railway Bridge.