The federal inventory of landscapes and natural monuments (BLN) is the first inventory required by the Law on the Protection of Nature and Cultural Heritage. This inventory is based above all on the inventory of landscapes and natural monuments of national importance (KLN inventory), which was developed between 1959 and 1988 by three private organisations – the Swiss Conservation Association (SBN, now Pro Natura), Swiss Heritage (SHS) and the Swiss Alpine Club (SAC) – and was first published in1963. Swiss landscapes are mainly land exploited traditionally, and marked in different ways. Really natural landscapes are hardly to be found any more except in the high mountains. Therefore, the landscapes included in the inventory are mainly those that have changed little, or are exploited in a near-natural way. Settlements are only included in the inventory in cases where they cannot be dissociated from the landscape.

A landscape or a site is recognised as being of national importance if its form and contents are considered to be unique in Switzerland, or especially typical of part of Switzerland. In evaluating a site, the approach is based on an overall view, using evaluation criteria for landscape typology and scientific aspects. Geographical, geological, biological, historical and aesthetic points of view are particularly important.