Groot Zeilmeer and Klein Zeilmeer are small natural lakes on the central Veluwe, just outside the village of Uddel in the municipality of Apeldoorn. They lie in a landscape of heath, forest and gently sloping sandy soils around the Uddelermeer and Bleekemeer.

Both lakes are classic pingoruïnes: depressions left behind after ice-cored hills from the last Ice Age melted and collapsed, forming shallow, roundish pools in the heather. From around 12,000 years ago these water-rich spots attracted hunter-gatherers on the Veluwe; archaeological research shows that groups of the Hamburg culture camped near Groot Zeilmeer, using the lakes and surrounding higher ground as a seasonal base.