Built between 1836 and 1842 by Bavarian architect Friedrich von Gärtner, Greece's Parliament was originally the royal palace. From its balcony, the syntagma (constitution) was declared on 3 September 1843, and in 1935 the palace became the seat of parliament. For history and politics geeks, the building is open by guided tour a few months of the year; book at least five days ahead.