Abstract Exploratory tests of ice penetration were made by driving small blunt cylinders into semi-infinite ice at normal incidence. Three types of laboratory tests were made: (1) drop-weight impact (impact speed 1.4–3.1 m/s), (2) high-speed ballistic penetration (impact speed 83–434 m/s), (3) deep penetration at low speed (0.42–4.23 m/s). Penetration by indenters and projectiles could be characterized by the energetics of the process, with little variation of specific energy as penetration speed changed by orders of magnitude. For blunt penetrators entering ice at −5°C, specific energy was typically in the range 1.5–15 MJ/m 3. Low speed tests provided data on penetration force (and energy) as a function of displacement. The test results were compared with other published laboratory data, and with field test results for bigger projectiles.