Ultima Thule

Ultima Thule (pronounced "thool") is the mythical farthest point north, the coldest and remotest spot on earth. It is also the name of the most inaccessble changer in Mammoth Cave, which McCombs brings to life in his poetry. The cave's limestone formations and the underground river that carves its spaces make a sort of echo chamber for the heartbeats of the author and his friends and neighbors, of whose lives the immense but buried cave is the dominant feature and metaphor.