Colne Valley Regional Park

East of the village of Denham, and west of the villages of Cowley and Harefield, and the town of Uxbridge, the Colne Valley regional park contains a mixture of farmland, woodland and water, 50 miles (80 km) of river and canal and over forty lakes, which help to regulate the flow of the major Thames tributary and provide fish for angling.

Popular attractions include Black Park, Chiltern Open Air Museum and the conservation area of Little Britain by the Grand Union Canal, Cowley.

"[8] High Speed 2 will pass through the north of the park on the 2.1 miles (3.4 km) long Colne Valley Viaduct.The viaduct is designed to resemble the flight of a stone skipping across the water.

[10][11] The protesters documented alleged environmental damage by HS2 workers over an eighteen-month period, voicing concern about the destruction of wildlife habitats and the possibility that an aquifer supplying drinking water might be affected.

[10] A couple living in a farmhouse on the route of the railway lost a seven-year legal battle in July 2020 and were compelled to move out after HS2 Ltd compulsory purchased their home on Dews Lane.