National Gallery of Ireland

For decades a dark religious painting hung in the dining room of a Jesuit house on Leeson Street in Dublin, thought to be a copy by a Dutch follower of Caravaggio. In 1990 a conservator from the National Gallery of Ireland, sent to clean some of the Jesuits' pictures, realised he was looking at the real thing, Caravaggio's Taking of Christ, painted around 1602 and lost for nearly two centuries. Judas leans in to kiss Jesus while armour glints in the torchlight. The Jesuits placed it on long-term loan to the gallery, where it is now the picture people queue for.

The museum opened in 1864 and grew partly on an unlikely income. George Bernard Shaw, the playwright, credited the gallery with much of his real education as a boy wandering its rooms, and he left it a third of his royalties. When his play Pygmalion became the musical My Fair Lady, the money poured in and paid for paintings for years.

Alongside the Caravaggio the collection is strong in Irish art, with a whole room for Jack B. Yeats, brother of the poet, and his loose, high-coloured scenes of Irish life.