A 500-acre open-air gallery filled with work by artists including Henry Moore and Tracey Emin has been named Museum of the Year.

The Yorkshire Sculpture Park, near Wakefield, was hailed by judges as a "truly outstanding museum with a bold artistic vision".

The park, which opened more than 30 years ago with an exhibition of 31 sculptures, welcomes 300,000 visitors a year to its galleries in the grounds of an 18th century country house.

It beat venues including Tate Britain and the Mary Rose Museum in Portsmouth to the £100,000 prize, formally known as The Art Fund Prize for Museum of the Year, at a ceremony at the National Gallery in central London.

Oscar-winning director Sam Mendes announced this year's winner and praised the "dedication, love, and unbelievable creativity" of the shortlisted museums which also included London's Hayward Gallery and the Sainsbury Centre for Visual Arts in Norwich.

Stephen Deuchar, who chaired the judges, said: "A perfect fusion of art and landscape, the Yorkshire Sculpture Park has gone from modest beginning to one of the finest outdoor museums one might ever imagine."

The award - formerly known as the Gulbenkian Prize until 2007 - was won last year by the William Morris Gallery in east Walthamstow, London.