Founded back in 1220, Saint Patrick's Cathedral in Dublin is the National Cathedral of the Church of Ireland. It's also the tallest church in Ireland, boasting a 43-metre spire and some pretty impressive Gothic architecture. A well on the grounds of the cathedral is said to have been used by St. Patrick himself to baptize Ireland's pagan population into Christianity. The grounds are also the burial site of the Anglo-Irish writer of Gulliver's Travels, Jonathan Swift. Today, the cathedral is one of Dublin's must-see landmarks for visitors to the Fair City.