Trains gain access to the station, which is in the central urban area of Lisbon, through a tunnel which is over 2.9 km (1.8 mi) long.

The Neo-Manueline façade dominates the northwest side of the square and is a Romantic recreation of the exuberant Manueline style, typical of early 16th century Portugal.

Its most interesting features are the two intertwined horseshoe portals at the entrance, the clock in a small turret and the abundant sculptural decoration.

The western wall of the train shed has a series of tiled pictures mixing classic religious themes with modern views of Lisbon.

On 3 May 2016, a 126-year-old statue of Sebastian of Portugal that stood in a niche between the entrance portals was accidentally destroyed by a person who knocked it over by climbing up for a photograph.