Annual and inter-annual end moraines. A preliminary report is given regarding investigations of De Geer moraines (the term introduced by Hoppe 1959). Detailed geochronological varve-measurements within a De Geer moraine series (fig. 1) prove that the opinion of De Geer (1932) according to which one can distinguish between annual and inter-annual moraines must be correct at least in certain areas. The investigations further confirm the opinion of G. Hoppe (1948) according to which De Geer moraines were built up at a calving ice-front. The annual moraines must be formed during winter-pauses in the calving, the inter-annual moraines during shorter pauses in the calving during the rest of the year. Detailed studies of the interior of several De Geer moraines show among other things that the ridges often have a coarse-grained core of washed till deposited directly on the normal basal till of the surrounding ground moraine sheet. In several cases such cores are overlain by lodgement till with fissile structure, but only on the proximal side and the crest of the ridges. De Geer moraines must have been built up at the base of the ice-front and cannot be simply classified as dump-, push- or lodge moraines. At least four stages can be distinguished in the formation of these moraines: washing (see above), pushing (inside structure), lodging (see above) and dumping (boulders on top of the ridges).