Sodankylä geophysical observatory (SGO) has operated in Sodankylä in northern Finland since 1913. SGO was originally founded by the Finnish Academy of Science and Letters. Now it takes care of national and international duties studying the space and geoenvironment as an independent research organisation in the University of Oulu. SGO performs long-term measurements, builds instruments, innovates and maintains domestic and international measurements, and performs research from these measurements. The seismic observations at SGO started in Sodankylä 1956. In 2005-2006 SGO seismic stations were updated to broadband instrumentation and connected to GEOFON data center. Today, the number of seismic stations has increased to 9. The stations have Streckeisen STS-2 or Nanometrics Trillium PA/PH broadband sensors. 3 of the stations are so called Posthole stations located in borehole 5-22 m below surface. The rest of the stations are located on the surface or in a more traditional type of vault. Data acquisition systems are either Earth Data PS6-24 digitisers and PC with Seiscomp or Nanometrics Centaurs. The continuous waveform data are collected at 100 Hz sampling frequency. The data are available from GEOFON data center. Further information about instrumentation can be found at the Institute’s web site (https://www.sgo.fi/). Waveform data are available from the GEOFON data centre, under network code FN, and arefully open.