Vocalisations – that is, sounds such as oh! or aaah – are highly versatile, obtaining their interactional meaning from the local environment. This study adds to previous research on vocalisations by showing how participants in video clips of mountain-bike crashes interpret the materiality of the ground in meaningful ways using such sounds. The vocalisations are called geomorphopoetic because they imitate the shape of the ground during movement. Three groups of geomorphopoetic vocalisations are identified: (1) sounds that inhabit the evenness and elongation of the ground, (2) sounds that inhabit the smallness of the ground, and (3) sounds that inhabit repeated movements supported by the properties of the ground.