Mértola Castle

Mértola Castle

A castle above a river port

In the far south-east of Portugal, where the wild hills of the lower Alentejo roll toward Spain, the river Guadiana winds through a deep valley. On a steep hill above a bend in the river stands the white town of Mértola, crowned by its castle keep. Long ago, before the river silted up, ships could sail all the way here from the sea, and Mértola was a busy river port — a gateway between the inland mines and the wider world.

A treasure-house of Islamic Portugal

Mértola is sometimes called a "museum town", and for good reason. Few places in Portugal hold so many remains of the centuries when this land was ruled by Muslims and known as part of al-Andalus. Under Moorish rule Mértola flourished as a trading town, and even became, for a brief time, the capital of a small independent Muslim kingdom.

The most remarkable survival is the town's main church. Look closely and you will see that it was once a mosque — one of the very few medieval mosques left standing anywhere in Portugal. Its rows of columns, its shape, and a beautiful prayer-niche, or mihrab, hidden behind the altar all remember its Islamic past. When the Christians took the town, instead of pulling the mosque down they turned it into a church, and so it has survived to amaze visitors today.

The Christian conquest

Mértola was won for Portugal in 1238 by the Knights of the Order of Santiago, a group of warrior monks who helped the kings conquer and hold the south. After the conquest, the castle was rebuilt and strengthened, and its strong keep was raised in 1292, looking out over the town and the river far below.

The knights and the king's officers ruled from the castle, guarding this remote corner of the kingdom and the valuable river trade.

Layers of history

Wandering Mértola, visitors walk through layer upon layer of the past: Roman foundations, Moorish streets and houses, the old mosque-church, and the medieval castle, all piled up on the steep hillside. Archaeologists have spent decades uncovering the town's many treasures, and several small museums display the finds, from Roman remains to beautiful Islamic pottery.

This rich mix of cultures — Roman, Islamic and Christian — makes Mértola one of the most fascinating small towns in the whole Iberian Peninsula.

Restored and protected

The castle, the mosque-church and the historic town are all carefully protected as national heritage. Mértola has won praise for the way it has preserved and celebrated its layered past, becoming a place where people come to learn about the many peoples who have called Portugal home.

Visiting today

Visitors who climb to Mértola Castle can explore the keep and walls, enjoy wide views over the white town and the green river valley, and then wander down through the old streets to the extraordinary mosque-church. The little museums tell the long story of this river port across many ages. Quiet, remote and steeped in history, Mértola is a place where the many layers of Portugal's past lie open to see.