The nucleus of the city is built on a ridge of rock (Mount Sceberras) which runs like a tongue into the middle of a bay, which it thus divides into two harbours, the Grand Harbour to the east and the Marsamuschetto to the west, which are subdivided again by three other peninsulas into creeks.
Pietro, forms a more or less protected basin, upon the shores of which are several small harbours (the most important being Carloforte), which are centres of the export of minerals and of the tunny fishery.
ASTROPALIA (classical Astypalaea), an island, with good harbours, in the south part of the Aegean, situated in 36.5° N.
The harbour of Vancouver is one of the finest natural harbours in the world.
Other small harbours on the lower Patagonian coast are not prominent, owing to lack of population.