Three new boreholes up to 25 m deep were drilled on Mount Reina Sofía (275 m a.s.l.), Livingston Island, where previous near-surface temperature measurements (mean annual ground temperatures of −2.1 to −2.6°C) have indicated the presence of permafrost. A thermistor chain and logging system were installed in the deepest borehole, while the others were equipped with individual miniature temperature loggers (iButtons). Initial data from the 25 m borehole indicates a permafrost body several decametres thick. Future data from these boreholes are expected to provide insight into ground temperature evolution in maritime Antarctica. Copyright © 2009 John Wiley & Sons, Ltd.