The dome of Agios Nikolaos’s church is distinguished everywhere and when you enter its interior you will feel the wonder. It was founded in 1849 in designs by G. Metaxas, and it was inaugurated in 1870. It is cruciform and mounted on an elevated courtyard with marble parapet. It belongs to the type of domed basilica.

It dominates in Ano Syros and it is the metropolis of the Catholics since 1652. It is a three-aisle basilica and it has a marble altar which was sculpted by a Tinian sculptor. It took its current form in the restoration that took place between 1832-1834, but in that point there used to be a church since the 13th century. It has many portable icons, statues of saints made by Italian artists, and frescoes. A beautiful light coming through the stained glass shines brightly upon it.

Near the Jesuit monastery they built the Capuchin monastery, which played an important role in the religious and social life of Ano Syros. The historical church of Agios Ioannis, a Catholic Metropolis of the island between 1639-1652, is located here. Beneath the church there are crypts which the people ran to when there were pirate raids.  

It is located in Ano Syros and in the building complex it includes the church of Panagia tou Karmilou (1581) which was considered to be the metropolis of the island up to 1639 under the name of Panagia tou Rodariou. The monastery, which was founded in 1744, has very interesting architecture and hosts the icon of the Virgin Mary, which is thought to have been transferred from Rome. It has a great library with old books, historical documents, manuscripts and parchments.  

The metropolis of Syros is the church of Metamorfosis (Transfiguration), the oldest one in Ermoupoli (1824) which has quite a few houses of the 19th century surrounding it. The church of Anastasi (Resurrection) on the hilltop of Dili was completed in 1909. It has a cruciform floor plan with a dome. In the interior it is divided in three aisles by a series of arches and pillars, it has quite a few Neoclassical elements and a throne. The numerous portable icons of the 19th century stand out. The church of Evangelistria. The parish church of the Catholics was built in 1829 at the position of an older church. It is a three-aisle basilica and the formation of the façade follows Italian standards. In the interior, two series of arches with marble columns define the three aisles.