Telescopio Nazionale Galileo, La Palma, Canary Islands, Spain, 2009. Several astronomical observatories have been built at Roque de Los Muchachos, the highest point on La Palma at an altitude of just over 2400 metres. The Telescopio Nazionale Galileo (TNG) is a 3.58 metre reflecting telescope operated on behalf of the Italian National Institute of Astrophysics. It began observing in 1998.