Open all year; closed 24 to 30 December inclusive. January and February: daily 9.30am to 4.30pm, last admission 3.45pm; March to 25 May: 9.30am to 5.30pm, last admission 4.45pm; 26 May to August: 9am to 6.30pm, last admission 5.45pm; September to mid October: 9.30am to 5.30pm, last admission 4.45pm; late October to December: 9.30am to 4.30pm, last admission 3.45pm. OPW gives no date for the switch to the late-October hours; the shorter day is stored for today. Guided tours take about 30 minutes and cost no more than the all-day ticket; booking online is optional (up to 28 days ahead, at most 9 tickets) and bus groups must pre-book. Free admission for everyone on the first Wednesday of each month, first come first served.
Access is limited: steep, high steps and narrow spiral stairs, low doorways and uneven walkways, with handrails to hold, so the upper parts of the castle are not suitable for wheelchairs or anyone unsteady; contact the castle before booking if in doubt. Toilets including a wheelchair-accessible toilet, a bookshop, baby changing and an audio-visual show on site; card payments accepted; no cafe at the castle. Children under 18 must be accompanied by an adult.
Photo: Cahir Castle's curtain wall, round tower and keep rising from the rock above the River Suir. Robert Linsdell, CC BY 2.0. Source: https://commons.wikimedia.org/wiki/File:Cahir_Castle,_Castle_St,_Cahir_(506765)_(28498329851).jpg. Licence: https://creativecommons.org/licenses/by/2.0. Resized and cropped for display; derivatives retain the source licence.