Galleries, museums and cultural spaces across the country have opened their doors to the public tonight for Culture Night.
Now in its fifth year, Culture Night takes place in more than 132 venues in Dublin, including the GPO, Leinster House, Royal Irish Academy of Music, the Science Gallery, and Croke Park.
Organisers say the purpose of the event is to turn the city and its cultural spaces into a public gallery for the evening.
Rather surprisingly, one of the most popular attractions on show proved to be the Freemasons' Hall on Molesworth Street.
Designed by British architect Edward Holmes in the 1860s, the Victorian building boasts a seriously spooky Egyptian-themed chapter room and a Knights Templar room designed as a medieval chapel.
"Big boy scouts with funny handshakes," said Richard Browne from Dundrum emerging from a tour of building.
Inside, one lady asked the curators how one got expelled from the organisation. "Atheism, breaking the law and non-payment of dues in the main," she was politely informed.
Not as mysterious as the rules governing nearby Leinster House, some might say, where people queued for tours for Dáil and Seanad Éireann.
Tom Kelly from Dublin, but who lives in the UK, described the tour as "brief, concise but informative". "It's fascinating to see the original interiors restored to the colour design of the 1760s."
However, he couldn't stay and chat as he had a busy itinerary, criss-crossing the city to visit several other venues.
The Ranelagh Arts festival opened tonight and runs through to Sunday October 3rd, with wide-ranging programme of talks, exhibitions and music gigs.
The festival was opened by Lord Mayor Gerry Breen and veteran Hollywood star Maureen O’Hara, who recently celebrated her 90th birthday.
In Galway, the Druid theatre company screened its stage version of JM Synge's Riders to the Sea, while several dozen Galway authors who have published work in the past year celebrated the night in Charlie Byrne's Bookshop.
Two larger than life galvanised bulls were among the madcap participants in the Earwig Art Group's street theatre, while drama of a different kind took place in Blue Teapot Theatre company's premises on Munster Avenue.