Constructed from layers of timber, peat, stone, and brushwood, crannogs were built out into shallow water, making them difficult to approach without a boat and relatively easy to defend. They were homes, refuges, and sometimes places of considerable status, and many remain as low, reedy humps in the water, easy to overlook unless you know what you are looking at.

The Derrynamraher crannog sits within a part of Mayo that contains a significant concentration of early and medieval archaeological remains, a consequence of both the region's long habitation and the preserving qualities of its wet, boggy terrain. Crannogs in the west of Ireland were in use across a broad sweep of time, from roughly 1500 BC into the seventeenth century, with many seeing repeated occupation or modification across the centuries. The specific history of this particular example, its date of construction, who built it, and how long it was occupied, remains undocumented in publicly available sources at present.

What can be said with reasonable confidence is that the site exists and is recorded as a monument, which offers a degree of formal protection. For anyone travelling through this part of Mayo with an interest in early settlement patterns, it is worth knowing that crannogs are often most visible from the water's edge in late summer or early autumn, when vegetation levels drop and the outline of the island platform becomes clearer against the lake surface.