The Goring Gap is a topographical feature on the course of the River Thames. The Gap is located in southern England where the river, flowing from north to south, cuts through and crosses a line of chalk hills in a relatively narrow gap between the Chiltern Hills and the Berkshire Downs. The Gap is approximately 10 miles (16 km) upstream of Reading and 27 miles (43 km) downstream of Oxford. The Gap is named after the town of Goring-on-Thames in Oxfordshire. That town is on the east bank of the river at Goring Gap, and Streatley (in Berkshire) is immediately opposite, on the west bank.
At Goring Gap, the Thames is at an altitude of about 45 metres (148 ft). The ground rises steeply on either side, reaching 100 metres (330 ft) within a kilometre to the east and west, and continuing to higher ground at around 160 metres (520 ft).
The Chalk beds have proved to be relatively more resistant to erosion than adjacent geological formations, so the relief of land to the north and south-east of the Gap is less marked. In particular, there is a low-lying Gault clay vale either side of Dorchester (to the north), and a broad, low-lying London Clay zone in the London Basin beyond Reading (to the south-east).
Although this configuration - of a major river slicing through chalk hills, with extensive areas of lower-lying land on either side - is not found in this precise fashion elsewhere in the Chiltern Hills, it is found at a number of locations in the North Downs and South Downs; for example, where the North Downs are crossed by the River Wey at Guildford, and by the River Mole near Dorking.