Deep structure of the crust and upper mantle of the northern, mainly Archaean part of the Fennoscandian shield, is poorly known, as the number of permanent seismic stations and controlled-source seismic profiles there has been always significantly lower compared to its southwestern part. However, even these rare studies showed that the upper mantle there is heterogeneous and seismically anisotropic. In order improve this knowledge, a temporary seismic array was installed in May 2007, and operated until September 2009. The array was a part of POLENET multidisciplinary project during the InternationalPolar Year. The research aims to obtain a 3D seismic model of the crust and upper mantle down to 670 km (P- and S-wave velocity models, position of major boundaries in the crust and upper mantle and estimates of seismic anisotropy strength and orientation) in northern Fennoscandian Shield. An important part of the LAPNET project is study of regional and local seismic events. In northern Fennoscandia, local seismic events are quarry blasts and weak earthquakes originating from re-activated ancient fault zones. These events can be used to create a 3-D velocity model of the crust, which is a necessary constraint in all studies using waves from teleseismic events. We present the first results of LAPNET seismic array research. The POLENET/LAPNET array was in operation from 01.05.2008 to 31.09.2009.The array consisted of 36 temporary stations deployed in northern Finland, Finnmark area of Norway and northern Karelia (Russia) and seismic stations of several permanent networks in Finland, Sweden and Norway. The POLENET/LAPNET data set includes: 1) Continuous data of selected permanent seismic networks in the territory of northern Fennoscandia that have the status of the DATA USED BY the IPY: a) Northern Finland Seismological Network (stations: OUL,SGF,MSF,RNF) b) Helsinki University Seismic Network (Finland) (stations: KU6,VRF,HEF,KEV,KIF) c) Swedish National Seismological Network (stations: KUR,NIK,MAS,DUN,LAN,PAJ,ERT,SAL,KAL,HAR) d) station ARC0 (NORSAR, Norway) e) Station KTK of the University of Bergen (Norway). Continuous data from these stations is not all available from the European seismic data centre ORFEUS, but will be specifically prepared for distribution in association with the LAPNET/POLENET experiment. 2) Continuous data of temporary seismic array installed on the territory of northern Finland, northwestern Russia and Finnmark area of Norway.