The Swords Round Tower dates from the 9th century and marks the site of an old monastery founded by St. Colmcille in the year 560 A.D. St. Colmcille blessed the local well of clear water, thus giving the town it's name 'Sord' meaning clear or pure. The Tower is reputed to have held the remains of Brian Boru after the battle of Clontarf (1014 A.D.) before he was taken to Armagh to be buried. It is seventy-three feet high, fifty-two feet in circumference, with walls four feet thick. It contained five floors. Its present entrance which is level with the ground, is of more modern construction, as well as the roof and upper story; what appears to have been the original doorway is twenty feet from the ground, and but four feet high. The cross at the top of the tower was put there in the late 17th century to let people know that it was a Christian Tower.

All that remains of the 14th century church is the square belfry. The site of the old church was rebuilt upon by the Church of Ireland in 1811. This later church was designed by Francis Johnson in the Gothic revival style of the Chapel Royal in Dublin Castle. Church services continued into recent times until St. Columba's had to close for repairs. Services now take place at 11.30am on Sundays.

All overlook the village of Swords.