Many National Trust houses and gardens hold secrets ripe for exploring. Whether you are investigating a secret passage, baffled by a maze or intrigued by a resident ghost, you'll soon discover that there is more to the National Trust than meets the eye.

Here are just some of the exciting things on offer:

The singing monks

© NTPL / Andrew Butler

A visit to Fountain's Abbey may include a ghostly performance from the monks of the Chapel of Nine Altars, a glimpse of the blue figure that haunts the hall or you may spot a man emerging from the wall.

• Fountain's Abbey

The haunted castle

© NTPL / Andreas von Einsiedel

Powis Castle is reportedly haunted by the ghost of a man dressed in a hat and gold-laced suit. The castle's staff have often seen fleeting figures around the corridors and piano music has been heard floating from the empty piano stool...

• Powis Castle

For more spooky days out, visit our ghostly encounters page.

Get lost in Glendurgan and Grey's Court

© NTPL / Stephen Robson

Visitors of all ages will enjoy the challenge that the spectacular laurel maze at Glendurgan Garden presents, while those at Grey's Court will be mystified by the maze inspired by the call for people to 'help each other to solve the secret of the maze of life'.

• Glendurgan Garden
• Grey's Court

Perfect hideouts

© NTPL / Mark Fiennes

Residents of Oxburgh Hall must have had the perfect opportunity for playing hide and seek! The hall boasts a priest hole and secret doors which today's visitors to the hall can investigate.

• Oxburgh Hall

Beneath your feet

© NTPL / Martin Trelawny

For those who fancy a subterranean adventure, visitors can explore the servant's tunnel at Castle Coole in Northern Ireland, or the ex-military tunnel at the Old Battery on the Isle of Wight.

• Castle Coole
• The Needles Old Battery