A deep rotary core drilling project in 1957 at Site 2 on the Greenland ice sheet (76°59′N., 56°04′W.) provided ice core to a depth of 411 m. The vertical variation in bulk density, macroscopic structure, oxygen isotope ratios, ionic constituents, and extraterrestrial dust (black spherules) was analyzed, using both field and laboratory techniques. These data permit the direct estimate of annual accumulation layers in the core. Continuous stratigraphic measurements and observations were made over the upper 110 m of the profile, and detailed physical and chemical analyses were made on continuous 1.3- to 3.9-m core increments at 100, 200, 300, and 411 m depths. The average total ionic concentration in the ice sheet ranges between 0.65 and 1.35 mg/liter. The annual global mass deposit of black spherules varies from 2.10 × 105 metric tons in 700-year-old ice to 6.57 × 105 metric tons in 12-year-old firn. The oxygen isotope ratio variation provides the best means of estimating accumulation at depth. Results of the investigations indicate rates of net snow accumulation of 42.3, 34.2, 37.4, 41.1, and 41.6 g/cm2-yr at the surface, A.D. c.1773, c.1513, c.1233, and c.934, respectively. Accumulation data and other physical and chemical evidence allow climatological inferences to be made over the 10-century profile. The ice core record shows that snow accumulation and temperature in A.D. 934 were similar to that of today, followed by a gradual decrease in both to a minimum in accumulation about A.D. 1773 and in increase from A.D. 1773 to 1957 and following.