The most important monuments of the site are:
- The Castle. a) The fortification. The Frankish castle with the battlements and towers was founded by William II de Villeharduin and was later reinforced by the Greeks and the Turks. b) The walls. The two strongly fortified circuit walls were strengthened by tall, rectangular towers, dated to the Late Byzantine period.
- The Cathedral of St. Demetrios. It belongs to a mixed architectural type: it is a three-aisled basilica on the ground floor with a narthex and a bell tower (dated to the second half of the 13th century), and a cross-in-square church on the upper floor (added in the first half of the 15th century). The interior is decorated with wall paintings representing many different styles, dated to the period between 1270/80 and the first quarter of the 14th century. The wall paintings of the dome date to the 15th century.
- Church of Saints Theodore. It was built between 1290 and 1295 by the monks Daniel and Pachomios. It is of the octagonal type, with lateral chapels, and is decorated with wall paintings dating from the end of the 13th century.
- Church of Our Lady Hodegetria (the Leader of the Way). It was built in 1310 by abbot Pachomios. It belongs to the mixed architectural type with a narthex and lateral chapels and is decorated with excellent wall paintings, dated to 1312-1322, some of which are connected to the Constantinopolitan art.
- Church of Aghia Sophia (Holy Wisdom). Domed, cross-in-square, two-column church, built in the middle of the 14th century. It has side chapels and a bell-tower. Remarkable wall paintings are preserved in the sanctuary and the chapels.
- Monastery of Our Lady Peribleptos. The catholicon (main church) is a domed, two-column, cross-in-square church with chapels. Beside it stands the Tower-Refectory. The church is decorated with wall paintings of exceptional artistic quality, made by various artists of the third quarter of the 14th century.
- Church of Our Lady Evangelistria (of the Annunciation). Domed, cross-in-square, two-column church decorated with wall paintings of the beginning of the 15th century.
- Monastery of Our Lady Pantanassa (the Queen of all). The catholicon belongs to the mixed architectural type and has exterior porticoes and a bell tower. Fine wall paintings dated to ca. 1430 are preserved on the upper floor and in the sanctuary, while the wall paintings on the ground floor date from the 18th century.
- Palaces of the Mystras Despots (Kantakouzenoi and Palaeologoi). Large building complex, L-shaped in plan. It contains many buildings of different functions, erected in different phases between the 13th and the 15th centuries.
- Urban buildings. The most interesting of the urban buildings erected on the hill are the Palataki (Small Palace), the House of Frangopoulos and the House of Laskaris.