Exposure to radiofrequency (RF) radiation was classified as a possible human carcinogen, Group 2B, by the International Agency for Research on Cancer at WHO in 2011. Outdoor RF radiation levels were measured during five tours in Stockholm Old Town in April, 2016 using the EME Spy 200 exposimeter with 20 predefined frequencies. The results were based on 10,437 samples in total. The mean level of the total RF radiation was 4,293 μW/m2 (0.4293 μW/cm2). The highest mean levels were obtained for global system for mobile communications (GSM) + universal mobile telecommunications system (UMTS) 900 downlink and long‑term evolution (LTE) 2600 downlink (1,558 and 1,265 μW/m2, respectively). The town squares displayed highest total mean levels, with the example of Järntorget square with 24,277 μW/m2 (min 257, max 173,302 μW/m2). Measurements in the streets surrounding the Royal Castle were lower than the total for the Old Town, with a mean of 756 μW/m2 (min 0.3, max 50,967 μW/m2). The BioInitiative 2012 Report defined the scientific benchmark for possible health risks as 30‑60 μW/m2. Our results of outdoor RF radiation exposure at Stockholm Old Town are significantly above that level. The full report can be found here.