Walking on a live volcano might sound like a foolish persuit, but it is possible to do this once in a life time activity at New Zealand's largest active cone and only active marine volcano, White Island.

When you step ashore on to this hissing, steaming and roaring ecological wonder - estimated at between 100,000 and 200,000 years old - you'll have entered a whole new world.

It is like walking on the moon. It is devoid of vegetation. It smells sulphuric and strange.

White Island (or Whakaari as it was named by the Maori before Europeans arrived) lies 48 kilometres off New Zealand's Bay of Plenty coastline - an 80 minute boat ride.

This active volcano and private scenic reserve is accessible by boat and helicopter. It is unique in that visitors to the island can walk right inside its main crater just above sea level with a minimum of physical effort and without undue risk. This allows you to experience at first hand nature's immense power as gas and steam burst up from far below the Earth's crust.

The surroundings are quite surreal and the scenery spectacular. It is like walking on an active volcanic moonscape with no plants or vegetation inside the crater. The smell of sulphur and the noise of steam emanating from the many fumaroles both large and small makes for a amazing sensory experience.

The trip to and from the island is also memorable. By boat you are where sea and bird life abound and dolphins often swim alongside; or by helicopter where it is possible to see the full grandeur of White Island rising out of the South Pacific Ocean.

On the outer slopes of the island are large colonies of the majestic gannet. This beautiful bird nests and rears it's young here. The noise of these "rookeries" takes your attention as you approach the island and their presence is clearly marked like snow on points above the cliff-lined shores.

The island is closely monitored by New Zealand scientists, but nevertheless being a volcano the Island is not without its hazards. Licensed operators take visitors to the island and provide hard hats, masks and the supervision necessary when venturing this close to the breath and pulse of the earth.