The Goodwin Sands is a 10-mile (16 km) long sandbank in the English Channel lying 6 miles (10 km) off the Deal coast in Kent, England. The area consists of approximately 25 m (82 ft) of fine sand resting on an Upper Chalk platform belonging to the same geological feature that incorporates the White Cliffs of Dover. The banks lie between 8 m (26 ft) and 15 m (49 ft) beneath the surface, depending on location.[clarification needed] Tides and currents are constantly shifting the shoals.