A virtual visit to the Cathedral of Santiago de Compostela

The Cathedral of Santiago's Romanesque, French-influenced floor plan, also known as a pilgrimage church, is laid out in the shape of a traditional Latin cross with three aisles in the nave and transepts.

From east to west, the main nave is around 308 feet long on the inside. The transept is much larger than usual for a pilgrimage church, measuring around 206 feet from north to south, making this Spain's largest Romanesque church.

The central nave sits beneath a barrel vault, and there are groin vaults above the side aisles. The space below the high, vaulted roof is divided up by elegant semi-circular arches, which in turn support a triforium that gives the aisles a sense of slenderness and light that is unusual in Romanesque churches of a similar age. The light is further enhanced by the very large window on the Cathedral's main facade.

The location of the tomb of Saint James the Apostle just below the Main Chapel has meant that the Chapel's Romanesque structure has remained essentially unchanged. Today, it is dominated by the baldachin and the majestic piece of Baroque silverwork that surrounds the stone statue of the seated Saint James. The latter is the work of the workshop of Master Mateo, and is accessed via some steps from the ambulatory, and traditionally embraced by pilgrims.

The apostolic crypt is just below the Main Chapel. It consists of what remains of the Roman aedicula, or mausoleum, where the sepulcher containing the remains said to be those of Saint James and his disciples was discovered in the 9th century; and a small passageway and place for prayer. The urn containing the remains of the Apostle dominates this symbolic site, said to be the Apostolic sepulcher.

A 16th-century pulley system and rope are suspended from the octagonal dome over the transept, in front of the altar. This is the mechanism for the famous Botafumeiro. This Galician word for the Cathedral's enormous thurible means expeller of smoke.

The Holy Door, which was installed here in the 16th century, is only opened in Jubilee Years (years in which the feast day of Saint James, July 25, falls on a Sunday). Flanked by two figures from Master Mateo's stone choir, its bronze plaques were added in the Holy Year of 2004.

This is the central chapel in the ambulatory, and the earliest part of the Cathedral to be built, in around 1075. At the entrance are two founding capitals with Latin inscriptions: "This work was built in the reign of King Alfonso," and "This work was begun in the time of Bishop Diego." In ancient times, pilgrims to Santiago de Compostela would come to this chapel to confess in different languages, and to receive their Compostela certificate.

Construction of the Chapel of the Pillar began in the late 17th century. It was originally intended as a new sacristy for the Cathedral, but once work had begun, Archbishop Monroy reversed the decision of the Cathedral's Chapter, instead putting an altar dedicated to Our Lady of the Pillar there. Its intricately decorated marble features scallop shells and stars.

This chapel was built in 1521 by Canon Juan de Mondragón. It is also known as the Chapel of Piety or of Santa Cruz, the latter due to the fact that the Marquisate of Santa Cruz was its patron. The chapel is dominated by a magnificent altarpiece, which is the work, made in Seville, of the Burgundy-born Miguel Perrín. Made in 1526, this work in terracotta depicts the Mourning of Christ.

Bishop of Iria when the body of the Apostle was discovered, Theodemar's tombstone, dating back to 847, was discovered during the archaeological excavations that took place in the Cathedral in 1955. It is now located in a small space in the transept, along with a mid-15th century image of Saint James as a pilgrim, which belonged to Archbishop Nuñez de Isorna.

Located in a corner of the Basilica's southeastern side, this is a large, pre-Romanesque font. According to tradition, in the year 997, the horse belonging to the Muslim Andalusian military leader, Almanzor, drank from the font.

The Portico of Glory is the western entrance to this Romanesque cathedral. Designed by the genius Master Mateo, it is considered to be one of the greatest masterpieces in the world. Master Mateo combined French, Italian, and Spanish influences in creating this polychrome granite portico. Its stylistic features place it firmly within the transition to Gothic sculpture.

The portico features iconographic representations of the Holy Scriptures, and scenes of apocalypse and salvation, which were practical, easy to understand illustrations aimed at the faithful who entered this space. The inscription on the lintels tells us that the portico was installed by Master Mateo on April 1, 1188.

The museum was opened in 1928, and was Spain's first cathedral museum. Over time, it added to its collections, mainly with pieces taken from different parts of the Cathedral, its collection of movable cultural objects, and archeological finds from the Basilica itself. It now also includes access to unique, magnificent rooms that have been turned into display spaces, such as the Chapel of the Reliquary, the room known as El Tesoro (The Treasure), the Cloister, and the Gelmírez Palace.

The galleries devoted to Master Mateo's works, as well as the museum's tapestries and collections of silver are of particular note. The Botafumeiro (the Cathedral's thurible) is also displayed here when not in use.

The Cathedral Museum has a large collection of tapestries made by different artists, dating from a range of periods. They include four 16th-century Flemish tapestries featuring scenes from the Second Punic War, which are displayed in the Chapter Room. These tapestries are based on a series of studies by Giulio Romano and Giovanni F. Penni. Along with the rest of the collection, they were probably part of the significant legacy left by the renowned canon Pedro Acuña y Malvar in 1814.

The 16th-century Renaissance cloister was built in a style known as Plateresque, meaning silversmith-like. Its four large wings have a magnificent stellar vault ceiling and beautiful cresting, while the headstones of canons on the ground tell a fascinating story from the Cathedral's history. The old bells from the Clock Tower can be seen in the central area of the cloister, including the original Berenguela bell, which is noticeably cracked.

The Fons Mirabilis sits in the very center. This is a Romanesque granite fountain that previously stood at the Cathedral's northern entrance, known as the Paradise Door. According to the Codex Calixtinus, up to 15 pilgrims could stand around it at once, where they washed away the dust and dirt of the Camino de Santiago before entering the Cathedral.

This part of the cloister is home to numerous royal sepulchers, including those of Berengaria of Barcelona, Ferdinand II of Aragon, and Alfonso IX of León and Galicia. The altarpiece in the Chapel of the Reliquary features a significant collection of medieval and early modern silverwork, including some of the Cathedral's most important works of art.