The distribution of radiocaesium in natural soils in Estonia was studied by using low-background γ-spectroscopy. The average relaxation lengths for 1 3 4 Cs and 1 3 7 Cs were determined for 25 soil profiles from over 120 samples collected throughout Estonia. The average mass relaxation length values, ρ, are 42 ± 15 kg m - 2 for the Chernobyl fallout and 110 ± 30 kg m - 2 for the atmospheric nuclear weapons tests fallout.The distribution of the Chernobyl deposition is extremely uneven. About 60% of the total deposition ( 50 10 1 2 Bq of 1 3 4 Cs and 90 10 1 2 Bq of 1 3 7 Cs) has been recorded in north-east Estonia. The maximum 1 3 7 Cs deposition reached 40 kBq m - 2 in 1986, while the country-wide mean was 2 0 kBq m - 2 . The Chernobyl fallout approximately doubles the 1 3 7 Cs mean deposition from the nuclear weapons tests (2 2 kBq m - 2 in 1986) in Estonia.