The Guia Fortress and Lighthouse are two iconic landmarks on the peak of Guia Mountain. The Guia Fortress was originally for the purpose of defense against foreign invasions and used as an observatory. When the Portuguese army withdrew from Macao in 1976, the fortress was opened to the public as a tourist attraction. Many of the bomb shelters underground remain intact and is today known as the "Songshan Bomb Shelter Exhibition Gallery". The Guia Lighthouse is an ancient lighthouse along China's coastal areas. When a typhoon strikes, the Macao Meteorological Bureau puts out the corresponding typhoon signal at the fort to remind the public to prepare themselves.