This expedition to Iceland was concerned with ice depth soundings of the largest ice cap in Europe and involved both the development of impulse radar systems and the use of satellite survey equipment for locating experimental stations and ice depth traverses (Fig 1). Vatnajökull, which translated means ‘water-ice’, is a temperate ice sheet and measures approximately 140 km east to west and 100 km north to south, thereby occupying more space than all other glaciers in Europe combined. Ice depth studies had previously been limited to seismic experiments conducted during the French-Icelandic expedition of 1951 when some 33 individual soundings were recorded. A few gravitational studies have also been made. It was not until 1976, however, that a first glacier base profile was obtained by a joint Cambridge-Icelandic expedition using electronic equipment developed at the University of Cambridge (see Polar Record, Vol 18, No 115, p 375–77). From that expedition some understanding of the electrical properties of ice was deduced and it became possible to design equipment that, theoretically, could measure the deepest parts of the ice cap. It was agreed in Reykjavik, in July 1976, to carry out a joint expedition in 1977 using a Mark II British instrument to survey Vatnajökull, at least in part, time and weather permitting. Owing to unforseen difficulties it was only possible for Cambridge University members to carry out this work.