On Hoy, only the bonxies will hear you scream

Mark Rowe braves dive-bombing giant birds and wild Orkney weather for a bracing ramble round the rugged rocks of the North

'Be positive - it could clear up," said Alison, as we stood in the breakfast room of the Thira guesthouse, peering doubtfully through the sea fog to where the island of Hoy was supposed to be. Alison, the owner of a b&b which overlooks Hoy Sound, said "could" in a way that translated as "almost certainly won't".

The weather-related cliché about four seasons in a day is well-applied to Orkney. September is regarded as one of the better months to visit; you still have plenty of light, the weather can be more settled, and the midges, which appear to have evolved to drill through denim, have died down.

Hoy is one of the 70 or so islands that make up Orkney. It is easily reached by ferry from Stromness, one of the two small towns on what is locally referred to as Orkney's Mainland. This walk connects Moaness Pier on Hoy with the totemic Old Man of Hoy, 6.5 miles away. You have a couple of options. Take the ferry to Moaness pier from where you can walk to the Old Man of Hoy and back, a distance of 13 miles, which will take most people six hours or more. An attractive alternative is to walk all the way there, but take a minibus back from Rackwick to link up with the ferry, knocking off five miles. If you decide to do this, you should check the bus schedule with the tourist office at the ferry terminal in Stromness.

From Moaness jetty, walk up the asphalted road towards the valley. Hoy church stands 100m or so to the left. From the outside it looks to have fallen into disuse, and I was surprised to find the door open. The interior is stark, though there is some clever woodwork on the chairs and the pulpit; the church closed in 2001, but services are still held there occasionally.

Continue uphill and keep straight on, following the signpost for Rackwick when the road bears right. You are now entering North Hoy nature reserve, a paradise for bird-lovers, while mountain hares may skip across your path and wildflowers are abundant. The track becomes more like a moorland path as you reach Sandy Loch. The mist finally started to lift and the scenery was spectacular. To the left stood Ward Hill, the highest point in Orkney at 479m. The hill is presumably how Hoy got its name - from "haey", the Old Norse for High Island. Both Ward Hill and the whale-backed ridges that flank the right of the valley are wind-striped, scarred by frost and gales.

The track follows Rackwick burn downhill, passing the modest-sized Berriedale Wood, the most northerly native woodland in Britain. The path criss-crosses the burn, twice using modern black-painted bridges that seem out of keeping with the surrounding wilderness. It's an isolated spot, but an idyllic one: the water in the burn is clear and gurgles heartily.

You reach Rackwick, on Hoy's wild Atlantic coast, against a backdrop of heathery hills and steep cliffs. A small crofting community once lived here; recent attempts have been made to revive the deserted houses and there is a scattered community, but no shops.

The Old Man of Hoy is three miles away. Follow the sign-posted path up past Rackwick hostel. On your left is Rackwick folk museum, in an old croft building. Like the church, it looks disused but it houses a simple and oddly captivating collection of items and photographs.

The path climbs steadily but is always clear. After you pass through a stretch of boulders, there is a small path off to the left, which invitingly appears to lead to a cliff-top walk. I made the mistake of taking this path some years ago, and found myself slap-bang in the middle of the breeding ground for the great skua, known locally as the bonxie. A short spell of dive-bombing saw me off then. They are still there, patrolling the skies - 6kg parcels of feathered malevolence.

Twenty minutes of flat walking later, you come to the Old Man of Hoy, a spectacular 137m latticed rock stack on a basalt base, the remains of a collapsed natural arch once connected to the nearby red sandstone cliffs. He looks deceptively small in contrast with nearby St John's Head, which at 335m is among the highest vertical cliff faces in Britain. This is a tough landscape. More people have trekked to the North Pole than have successfully climbed these rock faces.

Kittiwakes, fulmars, guillemots, razorbills and puffins all breed here. The breeding season is over, but just about anything can show up at any time. This is an exposed spot: the grass is as neat and clipped as a golfing green but it is narrow, and the cliffs are sheer. Returning the same way, you should have time to sit by the beach at Rackwick, watching the bonxies duffing up the fulmars - one bops the fulmar on the head; a second flies from underneath and delivers a head-butt to the solar plexus. Nature, red in tooth and claw indeed.

GIVE ME THE FACTS

Distance: 8-13 miles, depending on whether you take the minibus from Rackwick.

Time: five to eight hours.

OS Map Explorer 462. This walk is included in a booklet of environmental walks issued by the Orkney tourist office (01856 872856; www.visitorkney.com).

Logan Air, a franchise of British Airways (08457 733377, www.ba.com) flies to Kirkwall on Orkney from Edinburgh, Aberdeen and Glasgow, with connecting British Airways flights to the rest of the UK. Fares start at £150 from London.

For ferry timetables and tickets contact Orkney Ferries (01856 872044; www.orkneyferries.co.uk).

Mark Rowe stayed at Thira bed and breakfast (01856 851181; www.thiraorkney.com), near Stromness, which offers rooms from £25 per person.