St. Patrick's Cathedral have a programme of family-friendly Halloween events for today. There's a range of children's activities, tours of the cathedral, a tour of the cathedral's graves, and finally at 4:30 pm a candle-lit organ recital. Most of the events do not require booking.
Family tickets: €15 (two adults and up to four children)
Adult admission: €5.50
Concessions and children over seven: €4.50
Children under seven: free
Well done to St Patrick's. I think it's great to see this sort of open and inviting use of such venues.