The ISOS Federal Inventory

• is unique in providing a national inventory of heritage sites.
• is ratified by the Federal Council after consultation with the cantons.
• assesses heritage sites on the basis of a nationwide standard.
• does not prevent local development but promotes sustainable urban planning.
• is published in book form.

Background

The Federal Inventory of Swiss Heritage Sites of national importance ISOS was developed on the basis of Article 5 of the Federal Act of 1 July 1966 on the Protection of Nature and Cultural Heritage (NCHA, SR 451). After hearing the views of the cantons, the Federal Council decides whether sites are to be included, reclassified or removed from the inventory. The inclusion of a site in the ISOS means that it warrants unrestricted conservation (Article 6 NCHA).

Inclusion criteria

The ISOS lists 1284 sites of national importance (as of 1st June 2013), in most cases permanent settlements of at least ten main buildings which are marked on the Siegfried map (topographical map of Switzerland) and appear with a place name on the map of Switzerland.

All the sites in the ISOS have been examined in a cantonal and regional comparison and assessed according to the type of settlement (city, small town/town, urbanised village, village, hamlet, special case) by representatives of the federal government, cantons and members of the expert ISOS Assessment Committee. Topographical, spatial and architectural-historical features determine the national importance of the site. The ISOS assesses the sites in their entirety by considering the relationship of the buildings to each other as well as the quality of the open spaces between them and the relationship of the site to the immediate and more distant surrounding areas.

The ISOS method

A special procedure was required to develop an inventory system that gives consideration to all types of settlements in Switzerland, from large cities to tiny hamlets. The ISOS method allows a wide range of sites to be considered. All heritage site records can be compared with one another and coordinated with the existing inventories of federal or cantonal monument preservation sites.

The ISOS is based on the present stock of buildings. The inventory process divides the sites into areas. Each area is assigned a conservation objective that combines proposals for preservation and classification. In implementing the conservation objectives, the intention is to ensure that the valuable features of the heritage sites - and consequently their national importance - are preserved intact. In addition to the conservation objectives, the federal inventory also makes proposals for sustainable planning so that the architectural heritage and special quality of the settlements can be preserved for the future.

Scope of application and limits

Due to the number, scale and comparability requirements of the heritage sites, the ISOS can only measure a site's external features. The federal inventory does not take account of any utilitarian, economic, sociological or political aspects, unless these find clear expression in the local architecture. Land-use plans are also not taken into account; their varying statuses and differences in cantonal law and validity would create a distorted picture of the situation in Switzerland.

Practical application

The aim of the ISOS is to preserve the qualities which make the sites listed worthy of national importance and to avoid irreparable damage being done to them. The ISOS should therefore systematically be taken as a basis when decisions are made regarding the preservation of monuments and sites of national importance and in spatial planning decisions which may affect the latter.

Publication

The ISOS is currently published in book form. ISOS publications are not only intended for specialists in heritage, architecture and planning, but also for everyone with an interest in Switzerland. The books on sites in the different cantons prove that compiling an inventory is not only important, but extremely interesting.

Additional Information to the Federal Inventory

During the initial inventorisation, a list of heritage sites of regional and local importance was established next to the Federal Inventory. These data are not updated in the course of the revision of the Federal Inventory.
Several cantons have given the heritage sites of regional and local importance a legal effect by incorporating them in their own legislation.