Enclosures of this kind are among the most common yet least understood monument types in the Irish landscape. The term covers a broad range of features, from prehistoric ceremonial ringworks to early medieval farmsteads enclosed by earthen banks or stone walls, and their purposes varied considerably depending on period and place. What makes An Tuar Glas quietly notable is precisely the absence of detail surrounding it: it has been formally recognised as a monument, assigned a record, and mapped, yet the substance of what it is, how old it might be, and what its earthworks look like on the ground remains, for now, undocumented in public-facing sources.

The townland name itself offers a small point of interest. An Tuar Glas translates roughly from Irish as "the green bleaching green" or "the green drying field", a tuar being a patch of ground traditionally used for drying or bleaching cloth or grass. Whether that name has any relationship to the enclosure or simply reflects a later agricultural use of the land is unknown. Mayo as a county contains hundreds of such earthwork monuments, many of them unexcavated and poorly understood, survivors of a landscape that was shaped and reshaped over several thousand years of continuous habitation.