PALMA is situated at the north-west of the Canarian archipelago, which
is an autonomous region of Spain, a few hundred kilometres from the coast
of north-west Africa. Shaped like a stone-age axe, La Palma is one of the
smaller Canary Islands, with a surface area of 706 sq km and a population
of 80,000. It is unusually steep in relation to its size, rising sharply
out of the sea. A ridge runs down the centre of the island from north to
south, and the entire mountain range exceeds 2,000 m in altitude.
The highest point on the island is the Roque de Los Muchachos (2,426 m),
the location of the Observatory.
The island's climate is sunny,
but with moderate temperatures all the year round at sea-level. The cool
north-easterly Canary current and trade-winds keep the island cooler than
one might expect given the latitude. On the mountain top, however, there
is greater seasonal variation of temperature, from 18°C in summer to
3°C in winter. Despite occasional extreme conditions in winter, the
telescopes are operational throughout the year.