The cathedral of St. Nicholas / Lala Mustafa Pasha Mosque is the largest medieval building in Famagusta and was commenced in 1300 AD. It must be noted that the great cathedrals of the Middle Ages often took more than 100 years to complete, so was St. Nicholas was completed about 1400.
http://www.cypnet.co.uk/ncyprus/city/famagusta/lala/index.html