Carrick-on-Shannon got its royal charter and its own town seal in 1607, in the same wave of plantation-era charters that James I scattered across the freshly subdued north and midlands. On older maps the place appears as Carrick Drumrusk or Carrikdrumrusk - the anglicised form of the Irish name, before time and the post office smoothed it down. Long before the charter the area was already old: an Iron Age fortification still stands in the vicinity of nearby Drumsna, and the townland of Corryolus on the Shannon takes its name from Eolais Mac Biobhsach, ancestor of the Muintir Eolais, the most famous of the ancient Leitrim sub-septs. The Battle of Áth an Chip, recorded after the Norman invasion, was fought near here. On the bend of the main street stands the small jail-house of the 1700s, and behind it the council buildings now occupy the site of the larger Old Gaol that replaced it in the 1800s and was finally demolished in the 1960s. Three annual fairs were held in the town through the nineteenth and twentieth centuries - on the twelfth of May, the eleventh of August, and the twenty-first of November - in the great Irish rhythm of cattle, hiring, and gossip.

Until the early 1800s, the head of navigation on the Shannon was downstream at Drumsna. Then, in the 1840s, came the great engineering push: extensive dredging, the cutting of the Jamestown Canal, new locks at Drumsna and Knockvicar, and at Carrick itself a new bridge in 1846 - the nine-arch stone bridge it replaced had itself replaced a wooden structure. Quays went up along the riverfront. For more than a century afterwards Carrick was a major depot for river trade. Timber, cement, hardware and especially Guinness stout came up the Shannon by barge from Dublin, Athlone and Limerick. The Grand Canal Company kept the trade alive until 1960, when commercial Shannon traffic finally died and the river was left to small boats and silence. The silence did not last. The Shannon-Erne Waterway, restored in 1994, links the Shannon north into the lakes of Fermanagh, and Carrick-on-Shannon sits squarely at the junction of the two systems - a tiny river port that has become the largest narrowboat-hire base in Ireland.

St Mary's, on the Main Street, is the town's Catholic parish church - Neo-Gothic, dedicated on 19 October 1879, designed by the Dublin architect W. H. Hague. Father Thomas Fitzgerald, who saw the church built, is buried in front of the Blessed Sacrament Altar in the chancel he commissioned. St George's, the Church of Ireland parish church on St Mary's Close, was transferred to its present site in 1698 and rebuilt in 1829. Its rector from 1869 to 1886 was the Reverend W. A. Percy - whose grandson, born and raised in Roscommon, was Percy French, the songwriter and watercolourist who would become one of Ireland's most beloved entertainers. Off the main street runs Priest's Lane, where Catholic clergy first dared to live openly after the easing of the Penal Laws. The lane is also said to have been, briefly, the home of Turlough O'Carolan - the blind harpist and composer who came to Carrick as a boy in 1684 with his family from Nobber in County Meath. The harp, the hymn, and the music-hall song all have roots here.

The old courthouse on the quay was rebuilt in 2005 as The Dock - an arts centre with a theatre, galleries, artists' studios, a coffee shop and the Leitrim Design House. Every July the town fills for the Carrick Water Music Festival; every April for Phase One, a festival of modern and electronic music. Down by the river, the Carrick-on-Shannon Rowing Club has been pulling oars since 1836 - the oldest rowing club in Ireland and one of the oldest anywhere in Europe. From its sheds came Frances Cryan, who rowed for Ireland at the 1980 Moscow Olympics and won the Irish ladies' single sculls eleven times. The town is twinned with Cesson-Sevigne in Brittany, which is appropriate - both are river towns where everyone has a boat. On a summer Friday the quays here are lined with hired narrowboats, their crews carrying ice and Guinness aboard, and from up the river the old trade route is once again wide awake, just for pleasure this time.