WHATEVER your idea of the perfect man cave is, this hole in the ground will surpass it.

Wine? 4000 bottles. Location? Waterfront. Spacious? Nine storeys so bring your mates.

The extraordinary 100m long cave deep inside cliffs above Tasmania's Derwent River is Australia's largest private cellar and is on the market for $3 million-plus.

Agent Brian Watchorn of Charlotte Peterswald Property in Hobart said the cave was built by a retired financier - the current owner - who wanted access to the beach, 100m below the cliff top.

"The owner didn't want to deface the cliff with a ladder or similar structure so he built a cave with a vertical staircase," Mr Watchorn said.

Mining specialists were called in to dig the tunnel which took more than six months to excavate.

The cave is a 20 minute drive from Hobart and can be accessed from the waterfront or cliff top by camouflaged doors.

Entry at the top through a heavy security door leads to a curved metal staircase which winds down four storeys to a grotto-like main cellar where a 32-seat banquet table is surrounded by wine racks. The rock walls and white ceilings are lit by discreet lighting.

Concrete steps lead further down into the ground to a kayak storage area and out to a promenade of untouched rocky foreshore and the water.

The cave has a bathroom and kitchen area. Above is 8 hectares of land with a 300sq m shed.

The cave is close to coral colonies and rock pools and little bays make it ideal for fishing, diving and snorkelling.

The marketing material says the property offers potential as a restaurant-tourism venture or vineyard.