Armagh

The first church on this site was in 445 and the present building is from the 13th century, but it's been wrecked and rebuilt 17 times. What you see now is mostly from the 1830s and 40s. The body of Brian Boru, killed in victory at Clontarf in 1014, was taken to Swords then interred at Armagh: a slab on the exterior wall of the north transept denotes the spot.

The oldest library in Northern Ireland, founded in 1771 by Archbishop Robinson. It has a rich collection of 17th- and 18th-century books, including Jonathan Swift's own copy of the first edition of his Gulliver's Travels with his manuscript corrections. You need a prior appointment to see most of these.

Built in Gothic Revival style between 1840 and 1904, the RC cathedral has an impressive interior, the mosaics and woodwork being especially pleasing. It's perched on a hillock and you approach via a grand exterior stairway. St. Patrick's is an active parish church, with Masses, weddings and funerals. Guided tours must be booked two weeks in advance.

Small museum of this infantry regiment, formed in 1881 and amalgamated into the Royal Irish Rangers in 1968.

Displaying local natural and social history, and art. The reference library has local archives, photo and map collections. Visitor information is also available at the museum.

It's a working observatory only open for arranged tours and planetarium shows.

There are neolithic and Bronze Age remnants here, but the main structure was built in 95 BC: a timber roundhouse 40 m in diameter, which was then packed with stones, set on fire and covered with earth to create the present mound. This seems to have been a religious sacrifice, not destruction of a defensive "fort". The small nearby roundhouse is a modern reconstruction. Other nearby sites are Haughey's Fort a Bronze Age ringfort, and King's Stables an artificial hollow that may have been used for washing horses and chariots.

19th-century country house got up like a Norman castle; it fell into rack and ruin in the 20th century, but in 2008 was converted to private dwellings. So you can't tour inside, the reason to come is for the extensive woods and parkland.