Round tower near the church site
A general reference describes a round tower in Clondalkin village, 25.6 metres high with its original conical cap, built as part of an early monastery around 790 AD. Its doorway faces east toward St John's Church, a Church of Ireland building on a different site, not the Catholic parish church covered by this entry. The relationship between the round tower and the present Catholic church building is not established by the sources consulted.