A method for estimating past UV radiation levels using measurements of total ozone, sunshine duration and snow depth was applied to Abisko, northern Sweden, and Helsinki, southern Finland. The method has earlier been applied to Sodankyla (Finland) and Davos (Switzerland). The performance of the method was, as in earlier studies, found to be satisfactory with, for instance, a seasonal correlation coefficient as compared to measurements of the order of 95%. By extending the available ozone time series into the past using climatological values of the total ozone column, we were able to make UV estimates all the way back to the early 20th century at both stations. Both at Abisko and Helsinki, the produced time series of estimated daily erythemal UV doses shows increases over the last few decades partly due to the diminution of the total ozone column, and partly due to variations in the sunshine duration. Over the period 1950-1999, a statistically significant increasing trend of 2.2%/decade was found for Abisko, whereas for Helsinki, a trend of 4.2%/decade (also statistically significant) was found for the period 1979-1999.