Dalkey Quarry, Granite climbing area and former quarry on Dalkey Hill, Dalkey, Dublin, Ireland.

Dalkey Quarry is a granite climbing area with three main sectors offering over 350 different routes on rock walls. The climbs range from 10 to 35 meters in height and span from beginner to expert difficulty levels.

Quarrying began in 1815–1817 to supply granite for the new harbour pier at Dún Laoghaire, the South Bull Wall and flagstones for Dublin streets. In the 1840s Bishop Michael Fleming exported stone to Newfoundland for the Basilica of St. John the Baptist, and in the 1860s a two-ton block formed the base of the O'Connell Monument. Work continued sporadically and ended in 1917; in 1914 the quarry passed to the council and most of it joined Killiney Hill Park.

All routes are traditional climbs; bolted sport routes are not permitted, though metal pegs are tolerated on the most extreme lines. The 2005 guidebook lists about 300 routes, while the online guidebook has over 350, including Indecent Assault, one of Ireland's first E8 routes, first ascended in 1995.

Enter the West and East Valleys from the main entrance on Ardbrugh Road, just off Dalkey Avenue. The Upper Cliffs are reached by the ridge between the valleys or by a tarmac path from the Killiney Hill car park, past an old signalling tower and down concrete steps. The Far East Valley is private and closed to climbing, and climbing near peregrine nests is banned in nesting season.

Granite from this quarry was shipped to Newfoundland in the 1800s and used to build the Basilica of St. John the Baptist. This connects Dalkey to an often-overlooked chapter of Irish-North American construction history.