The peninsula, together with downtown Zhuhai, sits on an island separated from the continent by distributaries of the Pearl River.

The Border Gate (Chinese: 關閘; Portuguese: Portas do Cerco) was built on the northern isthmus.

The longest axis extends 4 kilometers (2.5 mi) from the Border Gate to the southwestern edge, Barra (媽閣嘴).

In 1513, Portuguese explorer Jorge Álvares arrived in the Pearl River Delta, in the Shenzhen area, which he called Tamão.

In 1887, the Sino-Portuguese Treaty of Peking was signed, allowing "the perpetual occupation and government of Macau by Portugal".