The Mezquita was built from a visigothic basilica from the 5th century, reusing its materials, and is one of the few surviving Spanish rural mosques.
It is an oddly-shaped building, made of brick and stone in a trapezoid shape, probably because of the hilly terrain. The oration room has 5 naves, whose arches, like in the Mezquita in Cordoba, are perpendicular to Qibla. The central nave is wider than the 2 nearby, which are in turn wider than the 2 outer naves. The Mihrab has lost its paint, and looks quite archaic; only the brick and stone is visible. In the oration room, 16 undated tombs were found.
When Spain became Christian, many changes were made, including the addition of a central axis in accordance with the new religion. The old door and the North flank were also reconstructed. Despite these changes, the whole building still retains a rustic charm.
References:House of the Blackheads (Melngalvju nams) is a building situated in the old town of Riga. The original building was erected during the first third of the 14th century for the Brotherhood of Blackheads, a guild for unmarried German merchants in Riga. Major works were done in the years 1580 and 1886, adding most of the ornaments.
The structure was bombed to a ruin by the Germans June 28, 1941 and the remains demolished by the Soviets in 1948. The current reconstruction was erected from 1995 to 1999. Today the House of Blackheads serves as a museum and sometimes concert hall.