With the support of Roscommon Leader Partnership,  the Portrun Development Association aim to develop the Portrunny Heritage Trail.  The trail will display heritage information and images relating to the following sites: Portrun Harbour, St Diarmaid's Holy Well, Portrun Church and Graveyard, Inchcleraun Island, Shannon View School, Galey Bay and Castle, Cloonsellan Abbey and the biodiversity of the area. Directional signage will also form part of the Portrunny Heritage Trail.

Lough Ree – ‘Lake of the Kings’ –  is the second largest lake on the river Shannon.  The lake is almost 30km from Lanesborough in Co Longford to Athlone in Co Westmeath.  In addition to boating and fishing, water skiing, canoeing, rowing and windsurfing are some of the water sporting activities the area is renowned for and are carried out on the lake.

The island of Inchcleraun (Inis Cloithreann – Clothra’s Island) in the northern part of the lake is the site according to Irish legend that the great Queen Meadbh met her death while bathing. The Island had belonged to Queen Meadbh sister Clothra and was, legend tells, a favourite place for Meadbh to bathe. Apparently her nephew sough revenge for the slaying of his mother at Meadbh hand and so he killed her by a lump of cheese from a sling shot. Inchcleraun is also known as Quaker Island it is one of the largest and most historically interesting Islands on the lake.

It is also the site of a monastic settlement founded in 540AD, the early Christian era by St Diarmaid and contains the remains of several ancient churches which still stand on the Island.

St. Diarmaid (or Dermot) was the teacher of St. Ciaran, founder of the Ireland’s famous Clonmacnoise monastery. It was an important centre of Christian learning and pilgrimage.

Between 800 and 1300 the Island and its churches were repeatedly plundered and burned by invaders. One of the churches has an unusual feature called a clogas, or square belfry, which is attached to the main building.  Most churches of this era have round towers, which are separate from the main building – with the only other exception being the one in Clonmacnois.

The clogas is located on the north side of the Island, and is visible from the shoreline. The smallest church on the Island is called Templedermot, the largest being Templemurray. According to local superstition, any woman who enters Templemurray will meet her death twelve months later.

In more modern times families lived on some of the islands in Lough Ree up until the 1950s, when they were then moved ashore.