The present 1912-built lock replaces those at this point of the river to the immediate east dating from the late 16th century and that of 1772 built by the Thames Navigation Commission.

The lock is on the western side of the north–south flowing reach between the A4094 Maidenhead to Cookham road and Ray Mill Island.

The flash lock was located in what is now the main weir, with a winch to haul barges through on the west bank near the tip of Boulter's Island.

[4] The lock was timber-sided, and the work was overseen by Joseph Nickalls, who had designed a scheme of improvements to the river from Abingdon to Richmond, in preparation for obtaining the act of parliament.

In 1773 a resident landowner complained of trespass in his woods by barge crews who "very much misbehaved themselves by their indecent conversation and horrid oaths and imprecations.

By 1780 the lock was reported as being in as bad a state as Marlow, and in 1795 Phillips Inland Navigation complained of the deep hole and subsequent shoals caused by the force of water.

A separate contract for the masonry and millwright's work was given to Clarke and Moss, while carpentry and general labouring was done by men employed directly by the commission.

A moving ramp, consisting of wooden slats with chocks to prevent rowing boats from rolling over, was constructed to bypass the lock.

It is to this day the largest salmon in recorded history caught on the non-tidal River Thames and weighed 14lb's, measuring 97 cm's in length.

This is followed by Bavin's Gulls on Cliveden Deep with landscaped hanging beech woods on the escarpment above which hosts Cliveden, a grandiose mansion run by a visitors' and public hire charity which was in the 20th century a forum for a prominent set of individuals and scene of the John Profumo affair.

Nicholas Pocock, the marine artist, lived at 'Ray Lodge' and broadcaster Richard Dimbleby had a house on Boulter's Island.