Monastic round tower discovered in Derry

A monastic round tower has been discovered in the middle of Derry city, hidden in plain sight for centuries.
The monument, which is on the ground of Lumen Christi College was thought to the remains of a windmill tower.
However researchers from Queens University Belfast have discovered that it dates back to the 13th or 14th century.
The monument is the only medieval structure still standing in Derry.