Casino, Marino, Dublin 3
Designed for Lord Charlemont by Sir William Chambers, who never set foot in Ireland, this exquisite neo-classical gem is surprisingly spacious. From the outside, it looks as if it has just one room; in fact, it has 16 on three floors. Restored in the 1980s by the Office of Public Works, the Casino richly repays a visit. Open: Feb-Nov, times vary. Tel: 018331618. Prices: Adult £2/Child £1
Church of St Aengus, Burt, Co Donegal
This masterwork by the late Liam McCormick is the finest post-Vatican II church in Ireland. Its circular stonewalled exterior was inspired by the pre-historic Grianan Aileach nearby, prompting the architect to describe his creation as "my pagan building". The soaring roof lantern is located right above the altar within an interior of awe-inspiring serenity. Admission free.
Ceide Fields Visitor Centre, near Ballycastle, Co Mayo
By far the most appealing of the visitor centres developed by the Office of Public Works in the 1990s, it won an RIAI Gold Medal for its architect, Mary MacKenna. The striking deconstructed pyramid, rising above the cliffs, was chosen as an appropriate primal form in which to interpret the fossilised landscape of Stone Age fields in the foreground. Open: daily mid-Mar-Nov. Prices: adult £2.50/ Child £1. Tel: 096-43325.
Observation Tower, Smithfield Village, Dublin 7
Not since Nelson was blown up in 1966 has there been such an accessible vantage point offering a panorama of Dublin. The glazed pod atop the old Jameson distillery chimney gives visitors a completely new perspective on the fast-developing capital, both upclose and as far afield as Howth and Killiney. But be warned: the entrance fee is a steep £5/child £3.50. Open: Mon-Sat, 10 a.m.-6 p.m. Sun 11 a.m.-7 p.m. all year. Tel: 018173820
Waterfront Hall, Belfast
Designed by Robinson MacIlwaine, this circular building has become the symbol of the new Belfast. With its flying saucer roof and glazed front overlooking the Lagan, it cuts a dash day and night. Public areas open daily. Tel: 048-90334400