Visitors have a once in a year chance to explore the lush surroundings of a hidden haven in the Norfolk Broads this weekend and try their hand at a wild - but slow paced - sport.

Inspired by London 2012, staff at Heigham Holmes - the remote island run by the National Trust - are hosting the Limpet Games featuring their own version of the 100m sprint, a thrilling snail race.

The shelled molluscs will be taking to the 'track' on Sunday during the weekend of activities, which includes opportunities for visitors to explore the island's secretive surroundings that are only opened to the public once a year.

The outdoor fun begins on Saturday (August 18) with specially organised wildlife walks with the resident warden to look for marsh harriers, bitterns, cranes, dragonfiles and butterflies. These will run from 10.30am - 12.30pm.

Alternatively there will be a rare chance to visit the island during twilight hours, from 8pm - 10.30pm, to seek out some of its nocturnal residents including owls, moths and bats.

On Sunday (August 19), from 10am - 4.30pm, families can explore the nature reserve at their own pace on a self guided trail, while learning out the island's special history and its importance for wildlife in the Broads.

Other activities on offer include face painting, pond dipping and the dramatic snail racing, which gets set at 2.30pm.

Steve Prowse, warden for Heigham, said: 'We all know the importance of getting our families out and about into the fresh air, experiencing the outdoors and creating memories that will last a lifetime. So we've arranged a whole host of activities to engage with our younger visitors, many of which are on the National Trust's 50 things to do before you're 11 � list.

'It's a popular day out and we're really looking forward to welcoming more families to the reserve this year.'

The National Trust took on Heigham Holmes in 1987 and since then has worked with its tenant farmer to restore the farmland back to grassland, create dykes and pools and reinstate water levels - and the reserve is now an internationally important wetland.

? Access to the island is via a swing bridge at Martham Ferry. Parking is sign posted off Ferrygate Lane and Black Street, Martham. Dogs are welcome on a lead and light refreshment will be available.

To book one of the guided walks on Saturday email heigham.holmes@nationaltrust.org.uk or call 01493 393450.