The area of the core zone of a national park shall amount to at least:
100 km2 in the Alpine foothills and Alps;
75 km2 in the Jura and on the south side of the Alps;
50 km2 on the Swiss Plateau (Mittelland).
The core zone may be made up of unconnected sub-areas provided:
the total surface area of the core zone exceeds the minimum area in terms of paragraph 1 by at least 10 per cent; and
free natural development is guaranteed.
At least 25 km2 of the core zone shall be located below the tree line.
Part of the core zone may lie in a neighbouring foreign country provided half of the minimum area is located in Switzerland and the other requirements of this Article for the core zone are met.5
The buffer zone shall, as far as possible, surround the core zone completely. It shall have an area that is in appropriate proportion to the area of the core zone.