Situated on a 277-metre (909 ft) hill, commanding a strategic position over the vast plains of the Baixo Alentejo, Beja was already an important place in antiquity.

Already inhabited in Celtic times,[4][better source needed] the town was later named Pax Julia by Julius Caesar in 48 BCE, when he made peace with the Lusitanians.

When the Visigoths took over the region, they called the town Paca (a direct derivation or shortening of the Latin Pax or Pace-Augusta) which then became the seat of a bishopric.

It must have been abandoned by the Portuguese because in 1172 Gerald the Mercenary captured the town from the Muslims and before departing from it the medieval Arab city was reduced to rubble and left desolate.

The entire population fled to Mertola thus bringing a definitive end to Muslim inhabitation of Beja.

It stayed under Muslim rule [most likely only inhabited by a garrison] till 1234 when king Sancho II finally recaptured the town from the Moors.

[6] Due to its southernmost inland location with the descending winds of the subtropics and low precipitation, especially in summer, the city has a hot-summer Mediterranean climate (Köppen: Csa).

[12] The year 2005 was particularly dry in Portugal and Beja suffered devastating forest fires in the surrounding rural areas contributing to the desertification that affects Alentejo.

It was built, together with the town walls, under the reign of King Diniz in the 13th century over the remains of a Roman castellum that had been fortified by the Moors.

It consists of battlement walls with four square corner towers and a central granite and marble keep (Torre de Menagem), with its height of 40 m the highest in Portugal.

The square in front of the castle is named after Gonçalo Mendes da Maia or O Lidador, a brave knight killed in the battle against the Moors in 1170.

The entrance hall leads to the sumptuously gilded Baroque chapel, consisting of a single nave under a semi-circular vault.

The walls are covered with Arab-Hispanic azulejos with geometric and vegetal designs that are among the most important ceramic decorations in Portugal.

The archaeological collection of Fernando Nunes Ribeiro, donated to museum in 1987 after forty years of archaeological research, is on display on the upper floors: Visigothic and Roman artefacts, gravestones from the Bronze Age with antique writings of the Iberians and steles from the Iron Age.

Tourism has also importance due to sunny weather, a long history and many cultural attractions including a 13th-century castle and a number of museums.

The Portuguese wet lease airline Hi Fly operated its Airbus A380, purchased second-hand in 2018, from Beja, as well as other airplanes of its fleet.

[citation needed] A highway was constructed to link Beja to the deepwater port of Sines about 60 kilometres away.