Rinn Dúin, the fort of the promontory
Rindoon, the lost town
In 1227 a castle went up on St John's peninsula, jutting into Lough Ree on the edge of Norman-held territory - the work tied to Geoffrey de Marisco and the Anglo-Norman push up the Shannon. A town followed: a walled settlement of perhaps a thousand people, with a parish church, a hospital run by the Fratres Cruciferi, a mill and a harbour, trading between the Norman river towns and the Gaelic country beyond. A town wall close to two kilometres long was thrown across the neck of the peninsula, with a gatehouse and towers. From 1229 it was attacked again and again, and with the Gaelic resurgence of the fourteenth century it was sacked and slowly emptied; by 1342-3 it was described as in Irish hands. It was never rebuilt. What survived is extraordinary - castle, wall, gateway, a later windmill on the church tower, the church and graveyard - sitting in farmland with the lough on three sides. Some call it the Camelot of the Shannon. Access is across private land and has been on-and-off closed, so check first.
Old-growth oak on the lough shore
St John's Wood
Beside Rindoon runs St John's Wood, one of the largest and most intact ancient semi-natural woodlands left in Ireland - oak, ash, hazel that has held the shore of Lough Ree for centuries. A waymarked forest loop of around 5 km runs through it from a car park near the village. In late spring the floor goes blue with bluebells. It is a nature reserve, and unlike the Rindoon ruins it stays open to walkers, which makes it the dependable outing here when the medieval town is shut.
A ditch with a purpose
The canal
Lecarrow Canal was cut in 1840 by the Shannon Commissioners to float limestone from a quarry above the village down to the Shannon navigation at Athlone. It is short - about a mile and a half - and dead straight, dropping from the village to Blackbrink Bay on Lough Ree. It silted up within a couple of decades, was cleared in 1889, dredged again by the Office of Public Works in the 1960s and reopened to navigation in 1967. Today it ends at a rebuilt marina, and it is the reason a cruiser bothers to leave the open lough at all. The towpath is a flat, still, heron-watching sort of walk.