The area of Appiano dates back to the glacial period.
Appiano and Caldaro have once been covered by a glacier snout, subsequent erosions in the course of millions of years formed the soil in its present day appearance. In an intermediate glacial period, the valley of the Adige was formed. In Appiano and surroundings there are many geologic phenomenons dating back to periods of time of a long time ago. Mica slate, porphyry or tonalits, but also glacial fluting and sedimentations of moraines are testimonies of this period. Glacial fluitings and kettle basins can also be admired at the Gleif hill in S. Michele. The one behind the Calvario/Gleif church is by the way one of the most admirable in the surroundings of Appiano.
A fine sand prevails in the area of Riva di Sotto, S. Paolo and Missiano as well as in Warthal valley. It is considered a sediment of a lake, which formed about 12,000 years ago at the edge of the ceasing Adige glacier.
A further phenomenon dating back to those days are the ice holes of Appiano. It is not yet clear if the rockfall that caused this natural phenomenon has taken place in the Ice Age or one of the subsequent intermediate glacial periods. Today this phenomenon makes you admire high alpine vegetation in the surroundings. If you would like to know more about the ice holes, read the respective article to follow.