Stave churches were once common through Norway and other parts of the Northern Baltic region.    They are timber structures and feature distinctly Viking styles of architecture although they date from just after the Viking period.   Borgund stave church, seen in these photos is a particularly good example and dates from 1150.   The structures rely on a substantial core frame of pine posts, with a non-structural perimeter and clad with steeply pitched roofs.   The outside timber cladding is painted periodically with tar in order to preserve the life of the building.   They are of Christian origin and came just after the change from a Pagan belief system.   Internally, the buildings are dark with no formal windows.