The first evening at the Doctor's Bothy – a newly converted self-catering "eco cottage" set high on a hillside on the western coast of North Uist – I waved, as prearranged, to a friend in Canada. Below me was a small loch, the few scattered houses at Hosta, a crofting community, a stretch of machair, a beach of Caribbean white sand, a turquoise bay with little white breakers and then the ocean all the way to the Americas. I could see the Monach Islands, now a national nature reserve, sticking up five miles away, and if the sun had not been in my eyes I might have seen the islands of St Kilda, still further out.
North Uist is in the utter west, and the immense breadth of ocean creates the white beaches out of shells ground down and thrown up on the first landfall it encounters. This fine sand in turn creates the machair – the extraordinary fertile pastureland between shore and peat bog, one of the rarest habitat types in Europe. I was a little too early for the full glory of the carpet flowers (orchids and rarities such as Irish Lady's-tresses and Yellow Rattle) although there were primroses behaving like meadow flowers, spread out in the open grass, and in the rocks the sea pinks were flowering.
North Uist, joined by causeways to Benbecula and South Uist, forms the middle section of the archipelago of the Outer Hebrides, with Lewis and Harris to the north and Barra to the south – plus innumerable smaller islands. It is a substantial island – the 10th largest in Scotland – but it has a population of fewer than 1,500. This is partly because more than half the land area of North Uist is covered by water – fresh and tidal and unusual mixed ("brackish") lochs and lochans and pools which lie in low peat bogs and rough land. They make getting from here to there complicated and affect the light, which takes on a strange soft brightness in the sunshine.
North Uist is not very easy to get to. You can fly from Glasgow to Benbecula, but it felt contradictory to arrive on an eco-holiday by plane. The best route would be to go from Ardrossan to Arran by ferry, drive across that island; take the ferry to the Mull of Kintyre; drive up that beautiful coast and follow the road from Fort William to Mallaig. From there you can cross to southern Skye, drive through the Cuillin to Uig and finally catch the ferry to Lochmaddy on North Uist. In fact, though, I drove directly up the A82 and crossed over to Skye at Kyle of Lochalsh. This is also an impressive road, through Glen Coe, but it is not as much fun now there are bridges instead of the old tiny ferries at Ballachulish and on to Skye. You can also cross by ferry from Oban to Lochboisdale in South Uist.
Blue-green sea, white sand and sharp rocks, a lovely broken landscape illuminated by so much dark water, a sense of being at the very edge of the world and a long complicated journey give the islands an exotic flavour. There is a real sense of being somewhere else, somewhere other. Why go abroad? It was even sunny most of the time I was there and at this time of year the days are absurdly long.
The Doctor's Bothy was the right place to enjoy all this. It is itself fairly hard to reach – 20 miles of single-track road from Lochmaddy and then more than half a mile up an extremely steep, rough path. You are advised not to tackle this unless you have a 4x4, but I took my Renault Clio up at the beginning and end of my stay. For those of a cautious disposition, the owners provide a wheelbarrow to transport your luggage, but I was relieved not to have to use it.
The cottage had just been finished, but it is obviously going to weather in happily and belong in its amazing setting. Inside it is both lovely and functional, with a number of features – especially the wooden floors and a wrought-iron spiral staircase – using recycled materials, and outside there is a remarkably sheltered corner facing the enormous view. Its particular distinction is that it is off-grid: the power is generated on site by photovoltaic panels and a small wind turbine. (They create 150 watts per hour in the summer and this is stored in batteries. For guidance, a laptop uses 70w per hour and room lighting at the cottage about 12w. Water is heated by a coal-burning stove and the cooker and refrigerator with gas. Because of the limit in quantity and the basic mechanics of the inverter, you cannot run high energy-use appliances, so no iron, no electric kettle, no computer-game consoles.) This worked for me, though I am not sure why they did not install a slightly larger turbine or why they "wasted" power supplying a TV (40w per hour) which felt oddly out of keeping. This may not be the place for those needing modern luxury, but it suited me. I liked having cows inspect me through the windows, candle-lit evenings, and the soft glow of solar lights outside mirroring the moonlight.
Further afield there is plenty to do in South Uist – boat trips and whale or seal watches and craft studios and outdoor activities of most kinds; there is good fishing and even a golf course on Benbecula (but no clubhouse – you pay for your round in an honesty box). But I did none of this. I walked: across the vast tidal sands in a mist to Vallay, another mournful abandoned island; around Balranald, an RSPB reserve on the machair; to the Neolithic stone circle and along stretches of rocky desolate coast. I looked at the views.
The waders were on the beaches – lapwing flopping about in the sky with their ridiculous feathered crests; oystercatchers like smart butlers, busy and chic; dunlin, whose black underbellies make them seem to flicker in flight and ringed plover scudding along the wave edges; out at sea there were gannets and skua and duck and geese; and the photographer, who was up the one decent-sized hill on the island, had a close encounter with a pair of golden eagles apparently inspecting my terrier's dinner potential. Meanwhile I was sitting at the bottom, in the sun, by a loch and failing (as usual) to see any otters, although their footprints were clear in the sand, along with deer, fox and sheep. I want to go there again – it was magical.
How to get there
The Doctor's Bothy, Baleloch, North Uist, sleeps four. High-season price per week £475, April-October. Bookable through Unique Cottages (01835 822 277; unique-cottages.co.uk).
The ferry from Uig on the Isle of Skye to Lochmaddy on North Uist for a car and two passengers costs £67.40 with Caledonian MacBrayne. Visit calmac.co.uk for timetables.
Visit guardian.co.uk/travel for more advice and travel suggestions
• This article was amended on 15 July 2010. The original stated that the ferry to Arran leaves from Troon. This has been corrected.