Sliabh an Iarainn rises 585 metres east of the town, and its name - the Iron Mountain - is literal. The slopes hold rich iron ore that has been worked here for over three hundred years. The whole reason a town exists at Drumshanbo is the iron industry that grew up around it in the seventeenth century. Pig iron produced at the smelting works on the east side of the mountain was carried south across Lough Allen to the finery forge at Drumshanbo, where it was hammered into malleable iron and shipped onward by boat to Dublin and Limerick. Local tradition says the first ship built by the East India Company in Limerick was finished with Drumshanbo iron. The cost was the forests. A nineteenth-century county survey records that 'almost the whole country was one continued, undivided forest, so that from Drumshanbo to Drumkeeran, a distance of nine or ten miles, one could travel the whole way from tree to tree by branches.' Those forests were felled to make charcoal for the iron furnaces. In 1782 immense piles of cleared timber lay around Drumshanbo. The trees did not grow back.

Drumshanbo had a famine graveyard. Some five hundred victims of the Great Famine are buried at the famine-period burial ground outside the town. The original Catholic church here had stood on a site nearby since 1744; the present St Patrick's Church on the main street was built in 1845 - in the worst year of the Famine - and was dedicated specifically to commemorate Saint Patrick's first crossing of the Shannon near here. St John's Church of Ireland, a Gothic-style structure ornamented with a tower and pinnacles, dates from 1829. The Methodist church on the Carrick Road was built in 1860 over an earlier chapel from the 1760s. And the Poor Clare convent, also built in 1860, has held an enclosed community of Franciscan nuns ever since - women who pray the Divine Office in choir, never leave the convent except for medical emergencies, and maintain Perpetual Adoration of the Blessed Sacrament around the clock. Throughout the nineteenth and twentieth centuries, five fairs a year were held at Drumshanbo - 12 February, 12 May, 11 July, 6 October, 16 November. In 1925, the village had seventy-seven houses, of which seventeen were licensed to sell alcohol.

Drumshanbo has been quietly punching above its weight on the cultural circuit for decades. The Joe Mooney Summer School, founded in memory of the local county councillor and traditional-music enthusiast Joseph Mooney, has run every July since the 1980s and now attracts Irish music players from across the world. The school is named for a man who, in the words of the town, 'did so much to promote the cause of Leitrim and his beloved town.' An Tostal - 'the Gathering' - was a nationwide festival set up by the Irish Tourist Board in 1953 to bring emigrants home for spring. It quietly died out almost everywhere. Drumshanbo is the only place in Ireland where it still happens, every June, with the same emphasis on Irish music and local culture that the original festival had. The Sliabh an Iarainn Walking Festival in April uses the old iron-mining trails. The Teach Ceoil - 'the Music House' - at Acres Lake hosts informal music sessions. And the Eurovision-winning songwriter Charlie McGettigan, who co-wrote 'Rock 'n' Roll Kids' with Paul Harrington for Ireland's 1994 win, has lived in Drumshanbo since 1973.

The story that has most changed Drumshanbo in the present century is The Shed Distillery, opened in 2014 on the site of the old factory premises in the centre of town. It was the first new distillery in Connacht in over a hundred and one years, and it has become best known for Drumshanbo Gunpowder Irish Gin - a gin infused with gunpowder green tea and slow-distilled in a small copper still. The product is now sold in over eighty countries. The Shed employs over a hundred people in a town of just over a thousand. It has done what a hundred years of state-funded rural development plans for Leitrim mostly failed to do: it has given young people from Drumshanbo a reason to stay. The old Cavan and Leitrim Railway closed here in 1959. The nearest train is now fourteen kilometres away at Carrick-on-Shannon. But the cruisers come up the Shannon to Acres Lake, the walkers come for the Sliabh Liatroma, the gin tourists come for the distillery tour, and the music players come every July. Drumshanbo is in better shape now than it has been in living memory.