Four days in Lewis and Harris: Gaelic, treeless, and the best beaches in Britain

The castle across the harbour was built in the 1850s by James Matheson, who made a vast fortune trading opium into China and spent part of it on the island, and it was later owned by Lord Leverhulme of the soap company, who had large plans here that all failed. It now holds the island museum, and the reason to go is upstairs: six of the Lewis chess pieces, walrus ivory figures carved in Norway in the twelfth century and found in the sand at Uig in 1831, are here on long loan from the national collections.

The arts centre on the sea front is the cultural middle of the islands, with exhibitions, films, a cafe and Gaelic in the air.

Then drive fifteen minutes out to the headland at the harbour mouth. In the small hours of 1 January 1919 the Iolaire, bringing servicemen home from the war, struck the rocks a few hundred metres from the shore and more than two hundred of them drowned in sight of the lights of the town. Almost every village on the island lost somebody. The memorial stands above the spot and the place is very quiet.

The west coast road holds three sites within eight miles of each other, and together they cover four thousand years. Start at the stones, which stand on a low ridge above a sea loch: an irregular circle of thirteen tall slabs of Lewisian gneiss around a taller monolith, with avenues of stones radiating out in a rough cross. They went up between 2900 and 2600 BC, which is before the sarsens at Stonehenge, and a burial chamber was added inside the circle later. Peat had buried them to shoulder height until it was cut away in 1857.

Four miles on stands the broch, a drystone tower of about 200 BC still standing nine metres high on one side, with the double wall and the stair inside it exposed where the rest has fallen. It is free, unstaffed and you can climb into it.

Then the blackhouse village on the shore at Gearrannan: thatched, drystone, chimneyless houses of the traditional Hebridean kind, lived in until the 1970s and now restored, one as a museum and the rest as places to stay. Sit outside them and look west, and there is nothing between you and Canada.

Harris begins where the peat ends and the rock starts. The road south climbs over a pass under the highest hill in the islands, 799 metres of bare quartzite that can be climbed from a lay by on the main road, then drops to the little harbour town of Tarbert on the isthmus between the two halves of the island.

West of Tarbert the road runs down the Atlantic coast past the beaches, and they are the reason people come: Luskentyre and Seilebost, miles of white shell sand with turquoise shallows over it, backed by machair that flowers in June and July, and empty even in August. Park at the marked places, walk out and take a coat, because the wind does not stop.

The single track road out to Hushinish, north west of Tarbert, is the other thing to do here: fourteen twisting miles past a castle and a salmon farm to a white strand facing the open Atlantic, with the evacuated island of Scarp across the sound. On the way back, the distillery in Tarbert has been making gin since 2015 and whisky since well after that, and does a good tour.

One last thing on the way to the ferry or the airport. The blackhouse at Arnol, half an hour up the west coast, is not restored so much as preserved: a long low house of drystone and thatch where the family lived at one end and the cattle at the other, with a peat fire burning in the middle of the floor and no chimney at all, so the smoke works its way out through the roof and blackens the thatch, which was then stripped every year and spread on the fields as fertiliser.

The fire is still lit for visitors. Ten minutes inside it and your clothes will smell of peat for two days, which is the most accurate thing any museum in Scotland does.

Across the road stands the white house the family moved into in the 1920s, with a chimney, and the contrast is the whole social history of the islands in fifty metres.