Climate and availability of indigenous and imported resources characterized the development of architectural patterns in Bangladesh. Pre-Muslim monastic architecture followed an indigenous style with terracotta décor, emulating important influences of the period and the region. The Mughals brought about an fundamental change by introducing elements of central dome, arches and tall central entrances. The European style was first observed in the churches of Dhaka and then in other buildings. At the turn of the nineteenth century, a hybrid of Mughal and European styles emerged. Modern architecture in its diverse form started appearing only in the 1960s.