We discuss collapse sinkholes occuring since 2004 on the sports field of Münsterdorf, a village north of Hamburg. The sinkholes, 2–5 m in size and about 3–5 m deep, develop in peri-glacial sand, with a likely origin in the Cretaceous chalk, present at about 20 m depth. The area has been analyzed with geophysical and direct-push-based methods, from which material properties of the subsurface have been derived. The properties have been used for mechanical models, predicting the subsidence.