Grutas do Rossio

Moorish Caves

Useful Information

Location: Alvia city center. Entrance at the backside of the Ermida de Sao Sebastião.
Open: Summer daily 9-12, 16-20.
Winter daily 10-12, 14-17.
Only after appointment.
Classification: SubterraneaRock Mines
Light: LightIncandescent Electric Light System
Guided tours:
Photography: allowed
Accessibility: no
Address: Posto de Turismo, Rua dos Lobos nº 13, 7920-000 Alvito, Tel: +351-284-480-808. E-mail:
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.


13th century begin of millstone mining.
1628 millstone quarry closed.


The Grutas do Rossio are underground millstone quarries located below the town Alvito. A local legend tells, that these tunnels connected the the houses of all wealthy families of the town. The millstone quarry was operated between the 13th century and 1628, and the millstones were of national fame. Other say that stones from this mine were used for ballast of ships during Portuguese discoveries. The caverns were forgotten for a long time, but were rediscovered in the 20th century. Some unfinished millstones can still be seen in the tunnels.

Alvito was under Muslim rule until the 12th century. Many of the houses and the Ermida de Sao Sebastião were actually built by the Muslim rulers. Indirect documentary notes, which were recently found, suggest that the tunnels were originally created as alternative exits from the old Moorish castle and other important buildings. This would make the origin of the tunnels even older. Templar documents describe the tunnels as Moorish limestone quarries excavated by enslaved labor. In 1190 King Dom Sancho I arrived in Silves, and Alvito was the center of the Muslim resistance under Ya'qub Al-Mansur. Its quite obvious that they would use the captured Christians to mine limestone for the fortifications. D. Frei Pedro Álvares, eighth Master of the Temple in Portugal, led an attack on Alvito. He managed to deceive the enemy and free the entire slave population, the reason why he is still known as Hero of Alvito.

This part of town is called Rossio de São Sebastião. The simple building was converted into the chapel of a Mudejar hermitage in the 16th century. It is famous for the frescoes which are probably painted by José Escobar in 1611. And at the rear side of the old chapel is a huge door, which seems to lead into some kind of cellar. Even many locals do not know that this is the entrance to the millstone quarry.

Recently a part of the structure has collapsed. This raises dangers for the buildings and inhabitants of the town. The caves are property of the city council but the complexity of the necessary stabilization seems to overexert the municipality.