The four longest rivers are the Essequibo at 1,010 kilometres (628 mi) long, the Courantyne River at 724 kilometres (450 mi), the Berbice at 595 kilometres (370 mi), and the Demerara at 346 kilometres (215 mi).
The Corentyne river forms the border with Suriname.
At the mouth of the Essequibo are several large islands, including the 145 km (90 mi) wide Shell Beach lies along the northwest coast, which is also a major breeding area for sea turtles (mainly leatherbacks) and other wildlife.
The local climate is tropical and generally hot and humid, though moderated by northeast trade winds along the coast.
CARICOM, of which Guyana is a member, is headquartered in Guyana's capital and largest city, Georgetown.