Lerras langs Mærradalsbekken nedenfor Ullernchausseen.
MetadataVis full innførsel
- Artikler 
A considerable weight of ballast placed on the slope of the valley beneath Ullern in Aker caused a slide on the 31st of March 1936. A big flake of the clayey ground turned so that its upper part sunk 2-3 m along a 70 m long crevice, while its lower part rose to a similar height at the bottom of the valley. The stream was dammed, and eroded a new bed. By prohibiting further depositing of ballast at the place the ground had the required rest.