Today, the Old Town of Porvoo is an icon of a historic town in Finland. The town was established around the church during the 14th century. The main, slightly curved streets run parallel to the river. Further medieval features include the block division, where the blocks reach down to the river and the frontage of merchants' storerooms is by the river bank. The wooden buildings in Porvoo are younger than the urban structure, as they have been built after the fire of 1760. The Old Town of Porvoo has been a predecessor concerning safeguarding of Finnish urban heritage. The first plan with protection intentions for the area was approved in 1915. It appealed to good will of owners with new arrangements. Although the aim was at preserving, the impact would be in fact an eminent transformation of the area. The Planning Act of 1932 gave an option to declare an area of historical significance as the "Old Town", thus supporting preservation of consistent urban historical sites. The Old Town of Porvoo got this status, together with a new plan. The aim of the plan was declared to preserve the street lines, size and form of plots and scale as such. Some public stone buildings got conservation regulations as "cultural history under protection of town". The view towards the shore was considered worth for protection. As a consequence to this plan, the Old Town got new buildings, which' scale in principle fit the area, but not their materials, details or general design. In 1939 the Archaeological Commission (present National Board of Antiquities) started for the first time in Finland inventories of urban heritage in two wooden towns. In Porvoo, this kind of study was made in 1940ies. The analyses focused on some twenty selected buildings. The criterion for an elite building was the highest possible age and purity of style. The main focus was on the public buildings. The analyses aimed at assisting art historical research; to document buildings on file before demolition. The urban conservation in a comprehensive scale was not imaginable. The third' generation's plan was elaborated during the 1960's, when the threat towards urban heritage rose due to rapid structural changes in the Finnish society. The plan entered in force 1974. It included a comprehensive inventory, with three cultural value assessment categories; 1) important as such,2) important as part of the significant environment 3) no need for protection. The current plan was prepared by 1992. In the plan, the building area is defined mostly according to the existing buildings. New constructions are strictly regulated according to existing ones. Permission for demolishing a building can not be admitted before the building permit of the site is approved. The regulation that "sold" the conservation is that one can "furnish" rooms to attics outside the permitted building volume with certain preconditions. Interiors are not mentioned, and their protection is a problem. These plans provide a brief documentation for a review of the Finnish development of urban conservation by planning. Even by reading the plans, it is possible to notice a certain development of argumentation. The content of conservation has enlarged. It seems as if many "hard facts" hindering the conservation, such as traffic, demands of more sunlight and clear air, have changed. The "soft values"; the attraction and fascination of the past, traditions, magnitude of a historic townscape, have been quite permanent.
