Mountains that drop in tiers like rough grey wedding cakes. White, flat-topped, rounded, calceous rocks, a foot high or so, separated by grassy crevices, usually about wide enough to trap an ankle. A bleak land, impossible to ride a horse on, or graze sheep on, and walking is done hopping from rock to rock. Small flowers in the crevices that like the limy soil. The occasional portal tomb - portal implies a grand door, but these are small tombs - you would have to crawl to go under the portal, crouch even if you were a hobbit.
There are some giant burial mounds (barrows) in Ireland, but not in the Burren. Overgrazing stripped the soil two thousand years ago, and the land could only support a few outcasts or hermits, catching birds and rabbits. "Not enough water to drown a man, nor a tree to hang him, nor earth enough to bury him."
Nothing in that landscape brings to my mind any of Tolkien's descriptions. Am I forgetting a passage?
Barrow Wrights?