In 1975 and 1977, samples from snow, firn, atmospheric CO(2), plants, and penguin guano were collected near the Soviet Antarctic research station Molodezhnaya. The results of tritium, deuterium, oxygen-18, (13)C, and (14)C measurements are discussed. From the tritium, deuterium, and (18)O measurement results of a firn profile at the Hays glacier, a value of the accumulation rate of 30 g water per cm 2 and year could be evaluated. By means of (14)C dating, the age of penguin breeding places was determined to be 1500 ± 500 years. (14)C data from atmospheric CO(2) and plants are discussed in terms of the age of the plants.