The Chincha Islands are a group of three small island

Island

An island or isle is any piece of sub-continental land that is surrounded by water. Very small islands such as emergent land features on atolls can be called islets, cays or keys. An island in a river or lake may be called an eyot , or holm...

s 21 km (13 mi) off the southwest coast of Peru

Peru

Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....

, to which they belong, near the town of Pisco

Pisco, Peru

Pisco is a city located in the Ica Region of Peru, the capital of the Pisco Province. The city is around 9 metres above sea level. Originally the villa of Pisco was founded in 1640, close to the indigenous emplacement of the same name...

, 13°38′S 76°23′W. They were of interest for their extensive guano

Guano

Guano is the excrement of seabirds, cave dwelling bats, and seals. Guano manure is an effective fertilizer due to its high levels of phosphorus and nitrogen and also its lack of odor. It was an important source of nitrates for gunpowder...

 deposits, but the supplies were mostly exhausted by 1874.

The largest of the islands, Isla Chincha Norte, is 0.8 miles (1.3 km) long and up to 0.6 mile (0.965604 km) wide, and rises to a height of 34 m (113 ft). Isla Chincha Centro is almost the same size as its neighbour to the north, while Isla Chincha Sur is half the size of its neighbours. The islands are mostly granite

Granite

Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...

, and bordered with cliffs on all sides, upon which great numbers of seabirds nest.

The islands were once the residence of the Chincha people, but only a few remains are to be found today. Peru began the export of guano in 1840. Spain, not having recognized Peru's independence (it was not to do so until 1879), and desiring the guano profits, occupied the islands in April 1864, setting off the Chincha Islands War

Chincha Islands War

The Chincha Islands War was a series of coastal and naval battles between Spain and its former colonies of Peru and Chile from 1864 to 1866, that began with Spain's seizure of the guano-rich Chincha Islands, part of a series of attempts by Isabel II of Spain to reassert her country's lost...

(1864–1866).