Examination of the experiences of travels beneath the earth across twenty oral history interviews reveals UBSS members’ diverse attitudes – from delight to dread – towards the dark worlds beneath the earth. In the process, it uncovers the rich sensory experiences of their encounters with the subterranean. Many of these experiences converged around the adaptation of participants’ bodies to the new spaces that surrounded them, revealing a thorough symbiosis between the body of the caver and the physical world. For some, this symbiosis was facilitated via changing technologies, including changes in climbing equipment that allowed easier access to deep underground spaces, clothing that allowed for increasingly extensive expeditions, and lighting that enhanced the scale and scope of perception in the darkness. Through engagement with visceral testimonies, this paper will illustrate that embodied and emotional relationships between UBSS cavers, and their underworlds, were rich and unstable, changing across time, space and according to individual experience.