Tartu Cathedral (Estonian Tartu toomkirik) is one of the landmarks of the city of Tartu. The building is now an imposing ruin overlooking the lower town. In the small part of it that has been renovated is now located the museum of the University of Tartu, which the university also uses for major receptions.
The hill on which the cathedral later stood (Toomemägi or "cathedral hill") was one of the largest strongholds of the pagan Estonians, and the strategic nature of the site makes it likely that it had been since the earliest times. It was destroyed in 1224 by the Christian invaders of Livonia. Immediately after the conquest the Christians began construction of a bishop's fortress, the Castrum Tarbatae, on this strategic spot. (Parts of the old walls of the previous structures have since been revealed by archaeological excavations).
The construction of the Gothic cathedral on the north side of the cathedral hill was probably begun in the second half of the 13th century. It was surrounded by a graveyard and houses for the members of the cathedral chapter. The cathedral was dedicated to Saints Peter and Paul, who were also the patron saints of the city. It was the seat of the Bishopric of Dorpat, and one of the largest religious buildings of Eastern Europe.
The church was originally planned as a basilica, but the later addition of the three-aisled quire gave it the character of a hall church. The quire (in an early form) and nave were already in use by 1299. The cathedral was completed at the end of the 16th century with the building of the two massive fortress-like towers, originally 66 metres high, on either side of the west front. A wall separated the cathedral grounds and the bishop's fortified residence from the lower town.
In the mid-1520s the Reformation reached Tartu. On 10 January 1525 the cathedral was badly damaged by Protestant iconoclasts, after which it fell increasingly into decay. After the deportation to Russia of the last Roman Catholic Bishop of Dorpat, Hermann Wesel (bishop from 1554 to 1558; died 1563), the cathedral church was abandoned. During the Livonian War (1558–1583) Russian troops devastated the city. When in 1582 the city fell to the Poles, the new Roman Catholic rulers planned to rebuild the cathedral, but the plans were abandoned because of the ensuing Polish-Swedish War (1600–1611). A fire in 1624 compounded the damage.
In 1629 Tartu became Swedish, and the new rulers showed little interest in the derelict building, which during their time fell further into ruin and neglect, except that the burials of the townspeople continued in the graveyard well into the 18th century, while the main body of the church served as a barn. In the 1760s the two towers were reduced from 66 metres to 22 metres, the level of the nave roof, and made into a platform for cannon. The main portal was walled up at this time.
With the re-founding of the German-speaking University of Dorpat by Tsar Alexander I of Russia in 1802, the Baltic German architect Johann Wilhelm Krause was commissioned to build among the cathedral ruins the university library, a three-storey building erected between 1804 and 1807. At the end of the 19th century the northern tower was converted for use as a water tower.
In the 1960s the library building was extended and fitted with central heating. When it was replaced in 1981 by a new university library building, the old library became the home of the historical museum of the University of Tartu (Estonian: Tartu Ülikooli ajaloomuuseum). A thorough building conversion took place in 1985, when the 19th century interior was largely restored. Today the museum contains displays of important artefacts of the university's history, scientific instruments and rare books. The rest of the cathedral ruins and the external walls of the quire have been structurally secured and consolidated.
The city walls of Avila were built in the 11th century to protect the citizens from the Moors. They have been well maintained throughout the centuries and are now a major tourist attraction as well as a UNESCO World Heritage Site. Visitors can walk around about half of the length of the walls.
The layout of the city is an even quadrilateral with a perimeter of 2,516 m. Its walls, which consist in part of stones already used in earlier constructions, have an average thickness of 3 m. Access to the city is afforded by nine gates of different periods; twin 20 m high towers, linked by a semi-circular arch, flank the oldest ones, Puerta de San Vicente and Puerta del Alcázar.