The Church of Saints Peter and Paul (Agios Petros and Agios Pavlos) n Heraklion was built during the early years of the Venetian domination and served as the main temple of the monastery of Dominican order (Domenicani Predicatori). It is one of the oldest monuments of architecture of the Cistercian monks in the 12th century, both in Europe and in Greece. It is located at position Kastela, next to the sea walls of Heraklion, between the Venetian Harbour and the Gate Dermatas. During the Venetian era it hosted burials of the leaders of Candia (current Heraklion) and in the early years of the Ottoman Rule, Saint Peter was turned into a mosque in memory of Sultan Ibrahim.
It’s first church was single aisled with wooden roof with slightly projecting transept in front of the parsonage. The latter was rectangular, covered by two low vaults and flanked by two square chapels. The east side was not semicircular as usual, but square and adorned in all its width with a large trilobed opening. Until the 15th century, the Venetians gradually added four chapels in a row at the south side of the church. In one of them frescos belonging to the 15th century still survive, actually unique in the city of Heraklion. All these four chapels housed tombs. In the 14th century one more chapel was added and because of its large size, it has an extra entrance.
It is one of the oldest monuments in its class, with a wider European interest about the course of architecture in the 13th century and its presence both in Europe and in Greece. Another characteristic is the two-storey chapel of the sanctuary, something that has not been found in none monument of its class. The Church of Saint Peter was a model for the construction Church of St. Nicholas at Chania in the 13th-14th century. The features of the monument identified during the restoration works reveal affinities with same-era buildings of the same architectural form in France and Italy (Silvanes, Venzone and Rieti).
The building suffered extensive damage from earthquakes from the 14th to the 18th century. The architecture of the monument with large dimensions (54m long, 15m wide and 12m high) of the middle aisle, combined with the absence of buttresses, seems that contributed to the partial collapse three times by earthquakes in the early 14th century, early 16th and the 18th centuries.
Throughout the Venetian occupation, both inside and outside the temple, around the walls of the temple, there were burials of prominent political and spiritual leaders of Candia. The Monumenti Veneti nell isola di Creta by Gerola mentions that four dukes of Crete have been buried there: Marco Gradenigo (1331), Giovanni Morosini (1338), Marino Grimani (1348) and Fillippo Orio (1357).
With the advent of the Ottoman rule, Saint Peter was immediately converted into a Muslim mosque in memory of Sultan Ibrahim and a minaret was added externally to the southwest corner. Other elements of the Ottoman period that were revealed during the restoration works include the mosque's mihrab, the pebbled floors of the surrounding area and a ceramic kiln. Around the monastery with its imposing temple and its buildings, in the surrounding area of the temple (Castella), important relics of ancient historical phases of the city that belong to the periods of the Arab conquest, the Second Byzantine and the early Venetian domination have been revealed.
Before the discovery of the antiquities in the area of Kastella, there was a raisin factory and then an music center with the name "Kastella" from where the current name of the place comes from. As an exchangeable property, it was bought by the parish of Agios Dimitrios Limenos to operate as a church. Finally, it was decided by the Ministry of Culture to allow only its anniversary service on the feast of the Holy Apostles Peter and Paul and to remain a monument to be visited. In recent decades, both the church and some of the monastery's buildings have been restored, while the surrounding area has been expropriated and organized as an archeological site connected to the Venetian monastery.