It connects the Gulf of Tonkin on its west to the South China Sea on its east.

The strait is on average 30 km (19 mi) wide[1] with a maximum water depth of approximately 120 m (390 ft).

[citation needed] The strait was crossed by the People's Liberation Army forces in the spring of 1950.

The Guangdong–Hainan Ferry (part of the Guangdong–Hainan railway) carries rail cars and automotive vehicles across the strait.

A bridge or tunnel has been discussed, as of 2018, as travel by air or ferry can leave residents and visitors isolated when bad weather sets in.