The Colne Valley Park covers 43 square miles of varied scenery ranging from semi-urban to unspoilt countryside.
The area to the north of the M40 is a distinct valley with rolling chalk hills forming its sides. The wide valley bottom has a wetland landscape including the River Colne, Grand Union Canal and a succession of lakes. Ancient sunken lanes often link the settlements.
Between the M40 and the M4, the valley is less pronounced as the chalk slopes become more gentle, and this part of the Park has large blocks of woodland and many historic parkland.
The southern section of the Park consists of a flat plain created by the convergence of the flood plain of the River Colne and the Thames. This area is dominated by five large reservoirs with steep grassland slopes.
Historically the Colne Valley was essentially an agricultural landscape and significant areas of this have survived to the present day.
For more information on the landscape please see the Landscape Character Assessment.