Europe's oldest mosque could be in a medieval city in Spain, archaeologists have found. The study shows that the city's ruins date back to the 8th century, shortly after the Muslim conquest in Al-Andalus. At the beginning of the eight century, Umayyad commander Tariq ibn Ziyad led the Muslim conquest of Al-Andalus. The Iberian Peninsula was years later declared a Muslim territory after the Amazigh warrior defeated the Visigoths. Forty-five years later (756), Abd al-Rahman I, a member of the Umayyad dynasty and the founder of the Emirate of Cordoba, arrived in Al-Andalus and ordered, circa 786, the construction of a great mosque in Cordoba. His project was called the Great Mosque of Cordoba, or La Mezquita, which sits on the ruins of a Christian church. The latter was shared by Christians and Muslims following the Islamic conquest of the Visigothic Kingdom. Since then, La Mezquita, which was converted to a Roman catholic church (Cathedral of Our Lady of the Assumption) during the Reconquista, has been considered Europe's oldest mosque. However, a recent study has been trying to prove the opposite, or at least point out that the Cordoba mosque is not the oldest Muslim place of worship in Europe. A mosque in Reccopolis According to the new study entitled «Reccopolis revealed: the first geomagnetic mapping of the early medieval Visigothic royal town» and published by the University of Cambridge, another Spanish city might be home to the continent's oldest mosque. After mapping, Reccopolis, one of at least four cities founded in Hispania by the Visigoths, archaeologists managed to detect the main features of the medieval city. One of the astounding things that they explored is a mosque, science news website Live Science reported in June. Using a geomagnetic instrument, researchers discovered that the 1,400-year-old city, located near Madrid, has «walls and structures» that revealed much about its history. The same source, indicates that Reccopolis was built by a Visigothic king in 578. They also stress that the city was abandoned in 800, linking that to the Muslim conquest of the Iberian Peninsula. In Reccopolis, researchers realized that the city includes a «large building with a different orientation from all the other buildings on the site, toward Mecca», Live Science wrote. «The floor plan also resembles that of mosques in the Middle East (…) only excavations will be able to confirm that the building is indeed a mosque», a researcher told the same source, adding that building could be Europe's oldest mosque.