The Hays Glacier of Enderby Land is a small Antarctic outlet glacier with a “sack-shape” source region of as yet not exactly known southward extent and area (approximately 104km2). It has a uniform or slightly wavy longitudinal profile, an approximately 7 km wide calving front between 46°15’ and 46°20′E, and a partly floating glacier tongue, extending to the seasonally changing front (classification 424 118 according to UNESCO-IAHS, 1970). The longitudinal mean surface slopes are 5–8 m km−1on the tongue, 20–30 m km−1in the step-shaped central section, and 8–12 m km−1in the entrance region. The glacier is bordered to 15 km south of the front by about 500-m-wide serac belts, associated in some places with pressure ridges. It is distinctly separated from the continental ice sheet by three rock walls on the eastern edge. At the western edge the glacier has a secondary influx region of 40 km3area which is crevassed and feeds a well-defined tributary into the left part of the glacier tongue. The average flow direction of the glacier is north, changing to northnorthwest at the front. The outflow velocity is of the order of 1000 m a−1, and the annual iceberg production in Spooner Bay (the southeastern section of Alasheev Bay in the Cosmonaut Sea) is approximately 3 km3. The dynamic conditions along the glacier are inferred from geodetic, strain, and accumulation measurements, and using a modelled internal temperature distribution.