London - The Isle of Wight is an extraordinary shape. A three-dimensional image would resemble a top-heavy iceberg ready to topple over into the sea. Approach across the Solent and you berth in a low-lying, almost swampy world of marshes, lagoons and tidal mudflats, where huge estuaries quickly constrict and taper into minuscule rivers. Yet to the south of the island, rising like a breaking wave, are the high, whale-back chalk downlands. Beyond that, the island plummets abruptly into the English Channel.
I've arrived at Yarmouth on the ferry from Lymington with a fixed walk in mind, but lifting my eyes from shoreline to the downs, I change tack and impulsively work out a coast-to-coast, north-south walk. It's surprisingly easy to identify a route. The West Yar river gives its name to the ferry port and paths shadow it as it tracks inland. Swans and over-wintering dark-bellied Brent geese nudge around among the reeds and fringes of the river. The mouth of the Yar is huge enough to accommodate ferries and a sizeable marina, but I'm struck by how quickly the river withers to little more than a meandering stream.
The explanation lies deep in the ancient geological history of the island. The Isle of Wight was not only once much bigger, with those downlands rising higher and further to the south, but it was also connected to the UK mainland at a time when the Solent was a river rather than a passage of open water. As the sea slowly eroded the soft chalk hills to the south, the Yar was deprived of its original tributaries, leaving the river an emaciated shadow of its former self. The lopsided shape of the island means that the Yar, and all other rivers on the island, flow from south to north.
The meandering walking is flat, pleasant and easy. I pass handsome buildings that look as if they were once customs houses or mills, thick hedgerows and brambles. A fetching bank of woodland rises up to the west and there's the occasional church spire to complete a comforting picture. Further on, there is a delightful coppice with alders, ankle deep in bog-like dark waters.
Soon enough, the reeds and lapping water bank up against the foothills of the downs and at the Causeway I peel away towards those sweeping chalk ridges.
The footpaths lead me, a little surprisingly, through a links golf course, with large clumps of gorse and plenty of birds bobbing around. The views are pretty - to the east, the coastline swoops down below the Military Road while to the west it dips to Freshwater Bay, then rises sharply to Tennyson Down, where the lush grassy contours are fronted by the white cliffs, seemingly freshly painted with a gloss finish.
I drop down into Freshwater, following the road to the beautiful church of St Agnes. It was built only 100 years ago, but its thatched roof makes it a rarity. This, and its low-slung appearance beneath fields of grazing cattle, make it seem ancient.
I turn north, but rather than retracing my steps, seek out the infant River Yar, little more than a stream now. Footpaths direct me behind residential houses and suddenly it feels as if I've stepped into The Wind in the Willows. The path is a goats' track, though still reliable, but runs right by the edge of the river. I could do with a machete to push my way through the shoulder-high, overgrown reeds that spread out for several hundred metres from both banks.
In no time I'm back at the crossroads at the Causeway. I turn left and pass another of the island's beautiful and often overlooked churches. All Saints Church is much older than St Agnes and has an extraordinarily large and sprawling graveyard. If you explore it, take a ball of string with you to find your way out.
The path then heads due north, passing Kings Manor Farm Shop, which is a superb pit stop for cake and drinks. The final leg takes longer than I expect, as the path strays away from the Yar, through undulating woodland. Soon enough, though, the woodlands fade away and I'm looking across the Solent to the New Forest.
Mark Rowe travelled from Lymington to Yarmouth with Wightlink (0871 376 1000; wightlink.co.uk). It also operates services from Portsmouth to Fishbourne and Ryde. Other companies include Red Funnel (0844 844 9988; redfunnel.co.uk) between Southampton and East and West Cowes and Hovertravel (0843 487 8887; hovertravel.co.uk) between Southsea and Ryde.
Mark Rowe stayed at Raleigh Cottage, Seaview. A three-night break costs from £145 (about R1 700) per person with Wight Locations (01983 811 418; wightlocations.co.uk) including return Wightlink car ferry crossings from Portsmouth or Lymington.
For information on exploring the Isle of Wight's churches, visit wightlink.co.uk/churchtrail.
Tourist information: islandbreaks.co.uk
WALK OF THE MONTHISLE OF WIGHTTime: 4 hours
Distance: 7.5 miles
Map: OL 29 Isle of Wight
Directions: From Yarmouth ferry, cross the road to the rear of the car park and follow the paved paths to the Causeway. Turn left along the lane, then dog-leg across the road, following signs for Freshwater Way. After 150 yards, turn half-left following footpath F31. Follow this path right up on to the top of the down.
Bear right downhill and through Freshwater to St Agnes Church. Turn right along Black Bridge Road, and then left, following signs for Freshwater Way.
Take path half-right, signposted for Freshwater Way and Yarmouth, and follow the path through Freshwater to the Causeway. Turn left, pass All Saints Church, and turn right alongside the cemetery, past Kings Manor Farm Shop, and follow signs through woodlands to reach Yarmouth via Gasworks Lane and the A3054. - The Independent on Sunday