Dedicated to the Isodia of the Virgin Mary, it is externally a large-sized white three-aisled basilica on an unusually spacious site for old Rethymno. In its current form, the building is an architectural monument of 1844, when the old church on the same site was demolished and completely rebuilt. Among other things, the cathedral is famous for its unique wooden iconostasis from 1852, which has survived to this day.