The Weir is a play written by Conor McPherson in 1997. It was first produced at The Royal Court Theatre Upstairs in London, England, on 4 July 1997. It opened on Broadway at the Walter Kerr Theatre on 1 April 1999. It has since been performed in Toronto, Dublin, Belfast, Bolton, Bury St Edmunds, Hamburg, Boston, Philadelphia, Pittsburgh, Los Angeles, Chicago, Buffalo, Washington, D.C., Detroit, San Jose, Coalisland, and San Francisco.