Barkham Brook begins as a series of drains on The Moors, an area of woodland to the north of Finchampstead close to Sand Martins Golf Course.

[2] Between the moated site and the brook is the grade II listed church of St. James, an Early English style building the nave of which was constructed in 1862 by John B. Clacy and Son, while the chancel and transepts were added 25 years later.

[4] It was created by John Walter III, who extended an original pond after he bought the land to expand his Bearwood Estate in 1873.

It includes an area of wet heathland, where peat sits on top of an underlying layer of clay, resulting in a ferruginous swamp, characterised by rust-coloured iron bacteria.

[6] At the western edge of Longmoor Bog, the brook is crossed by Park Lane, and turns to the north along the perimeter of the former Arborfield Garrison, which closed in 2015 to be re-developed for housing.

Shortly afterwards, it is joined by the outflow from Bear Wood Lake, which is located in the grade II* listed parks and gardens belonging to Bearwood College.

John Walter II bought the Bearwood Estate in the early 19th century, and employed J W Sanderson to build a classical villa.

[13] The brook continues in a north-westerly direction, until it almost reaches the River Loddon, but then turns to the north-east to pass under the M4 motorway embankment in its own culvert.

The main reasons for the water quality being less than good are discharges from sewage treatment works, and physical modification of the channel, mostly in connection with land drainage, which presents obstacles to the movement of fish around the system.