Written by Jack Guy, CNN

Archeologists have uncovered the remains of a 12th century bathhouse at a popular bar in the city of Seville, southern Spain.

Cerveceria Giralda has been operating in the heart of the city since 1923, but the bar is housed in a building with a far longer history.

While the vaulted ceilings suggested it could have been a bathhouse, and historical records said there had been one in the area, no one had found concrete evidence of its existence, archeologist Fernando Amores of the University of Seville told CNN Thursday.

Now skylights and red geometric paintings dating from the 12th century have been uncovered during recent renovation work.

Restoration of skylights and painting found underneath decoration installed in 1920.

Restoration of skylights and painting found underneath decoration installed in the 1920s. Credit: Fernando Amores

In the 12th century, Seville was ruled by the Almohad caliphate, a North African Berber Muslim empire, which controlled much of the Iberian peninsula — modern day Spain and Portugal — at the time.

Amores was part of a team of experts that collaborated on the restoration of what he called a “very unusual” find.

The skylights are made in the form of eight-pointed stars, and the red ocher paintings make up interlinking geometric patterns.

Roof in cold bath room with new lighting.

There are four kinds of skylights in different sizes. Credit: Fernando Amores

The star-shaped windows are typical of hammams, and there are four different kinds in different sizes, said Amores. However, the fact that the paintings completely covered the walls and ceiling is unusual, he added.

“It forms a beautiful sky,” said Amores, with light streaming through the windows reminiscent of the stars at night.

The complicated craftsmanship shows the importance of the bathhouse, which was located close to the city’s main mosque when it was built, he said.

There is more restoration work to be done, said Amores, but additional funding will be needed.

Archeologists are also carrying out carbon dating on the stucco — a fine plaster — to get a more precise date of construction, added Amores.

Star-shaped windows are typical of hammams.

Star-shaped windows are typical of hammams. Credit: Alvaro Jiménez

The project has been a collaboration between the owners of the building, the owners of the bar and the team of archeologists, said Amores, explaining that the whole process has been a triumph of cooperation.

“We are very happy,” he said.

The owners decided to carry out some renovation work last summer, a spokesperson for the bar told CNN. Until then, the original features had been covered up by a layer of decoration installed at the beginning of the 20th century.

As the work revealed evidence of the bathhouse, archeologists were brought in to supervise, the spokesperson added. The baths had at least three rooms, they said, which are now used as a kitchen and two dining rooms.

Architect Francisco Diaz told local TV station Canal Sur that archeologists didn’t initially find anything of interest, but then one skylight was found in the ceiling. “From there it was like drawing back a veil and all of the skylights started to appear,” said Diaz.

Cerveceria Giralda serves tapas and beer, and is well-known in Seville.

“We think it (the bar) could open to the public in a month, combining restaurant operations with possible visits at certain times,” said the spokesperson.