Brilliant churches, as well as male and female monasteries were built in Heraklion, especially during the rich Venetian Era. The seat of the Latin Archbishop was the church of Apostle Titus, which was built during the second Byzantine period and later. Heraklion today hosts the Archdiocese of Crete which operates under the jurisdiction of the Ecumenical Patriarch in Constantinople.
The Museum of Byzantine Icons and Relics of Archdiocese of Crete is located in the Venetian church of St. Catherine of Sinai, in the center of Heraklion and next to the cathedral of Saint Minas.
The Municipal Gallery of Heraklion is hosted in the Basilica of Saint Mark in the center of Heraklion, just opposite the famous Lions’ fountain. The basilica was built by the Venetians in 1239, was destroyed by an earthquake in 1303 but restored immediately,
During the second Byzantine period, as the largest and prime official church in the city of Chandax, St. Titus became the seat of the new Orthodox Diocese of Crete. The Venetians later installed a Catholic archbishop and converted the church into a Catholic cathedral.
Saint Minas is the patron saint and protector of the Grand Castle (Heraklion) and its past combines legend with tradition and the town's history. It was built in 1862, next to the smaller temple of Saint Minas.
Reference is made to the Chapel of St. Minas and the Virgin Mary Pandanassa in the inventories of Chandax churches in Venetian times. Having fallen into disuse for many years, in 1735 it was renovated to become the cathedral, thenceforth serving as the main centre for the Orthodox Christian faithful in Ottoman Chandax.
The Church of Sts Peter and Paul 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.
The Orthodox Church of Agios Mattheos (St. Matthew) of Sinai was built in 1508 on the ruins of an earlier Byzantine church. This was the main Christian temple after the conquest of Crete by the Turks, as the Turks converted the monastery of Agia Aikaterini of Sinai to a mosque.
The Church of Saint Demetrius near the Venetian harbor of Heraklion is built on the site of an older church of St. Demetrius, who was the patron saint of the carpenters of Heraklion during the Venetian era (every profession then had its patron saint!). The only surviving part of the initial church is a part of frescoes inside the sanctuary.