Newry

Built 1825-29 in neo-Gothic style, this was the first Roman Catholic cathedral to open in Ireland after the penal laws were relaxed, so its construction attracted many European craftsmen. The masonry is local granite, the stain glass windows are German and the marble altars and statuary are Italian. The cathedral holds a relic of St Teresa of Calcutta (Anjezë Gonxhe Bojaxhiu 1910-1997), a muslin cloth stained with her blood and set in a cross.

Built circa 1578, which makes it the first Protestant church in Ireland after the Reformation, but it was rebuilt in 1866. Still in use by the Church of Ireland, it's a distinctive part of the town skyline, with four little spires at each corner of its clock tower, atop a hill east bank of the river.

This was built in 1893 over the Newry (or Clanrye) River, the boundary between Counties Armagh and Down. The site was part diplomacy but also a creative use of space in a town divided by river and canal, and the building looks as if it belongs in Utrecht, if you can ignore the hills behind. (The bus station likewise spans the river.) The council offices have moved half-a-mile west to Monaghan Row, and the Town Hall now hosts the Arts Centre. This sometimes has art exhibitions but is mostly a performance venue.

How you can mislay an entire castle? A Cistercian Abbey was founded in Newry in 1153, with extensive lands. To the south was "The Pale", that part of Ireland directly ruled by the English monarchs. The abbey lands were literally beyond the Pale, but Edward III grabbed them anyway, dissing the abbey as "mere Irish, conversing only with such, and spending their rents and profits in abetting the said Irish". In the 16th century all monasteries were dissolved by Henry VIII. The lands were awarded to Nicholas Bagenal (1509-1591), who'd fled England as a wanted man for murder, but who rose to be Marshal of the Army in Ireland (and thrice fell and rose again). He demolished the abbey and built his own fortified house on the site. His direct family died out in the 18th century and his "castle" was sold to a merchant, becoming McCann's Bakery. Historians and map makers entirely lost sight of the place, though everyone at the bakery knew — the old human bones and medieval carvings were a clue. If only some historian had bought a bap here; but not until the bakery closed in the 1990s was the castle re-discovered. It's been partly restored and now houses the town museum.

This elegant thatched cottage was built in 1776 as a summer lodge. A pseudo-Georgian mansion was tacked on in the 20th century but demolished when the place was acquired by the National Trust. The Treaty Room is where the Anglo-Irish Treaty of 1921 was negotiated, but the interior is seldom open, you come for the extensive grounds and exterior view.