Muckanaghederdauhaulia (Irish: Muiceanach idir Dhá Sháile, meaning 'pig-marsh between two sea inlets')[2][3] is a 503-acre (204 ha)[1] townland in the civil parish of Kilcummin in County Galway, Ireland.

It is in the poor law union of Oughterard in the barony of Moycullen.

[5] There was a hamlet within the townland which had the same name in Irish (Muiceanach idir Dhá Sháile), but a shorter English name, Mucknasalia.

[9] The townland lies on a low, boggy peninsula in Camus Bay and can be reached by turning west from the R336 road at Cinn Mhara, or by going northwest on the R374 road out of Casla, then turning onto Bóthar na Scratóg and going north.

[10] The population recorded in those census reports which provided figures at townland level were as follows:[11][9] The area is mentioned in Georges Perec's novel Life: A User's Manual: "In between, there had been the little harbour of Muckanaghederdauhaulia, not far from Costelloe, in Ireland’s Camus Bay...".