[1][2][3] Keurusselkä gained international publicity in 2004 when a pair of amateur geologists discovered an ancient impact structure on the western shore of the lake.

The element keuru is a dialectal word meaning "crooked", in this context referring to the shape of the lake.

[2] In 2003, some fish near Mänttä still had caesium concentrations several times higher than in Olkiluoto and Loviisa, which host the two nuclear plants of Finland.

[2] The lake is considered good for fishing, and the pike (Esox lucius) and perch (Perca fluviatilis) populations are especially large.

[3] In addition to the shatter cones, microscopic studies of samples from a breccia boulder have revealed shock metamorphic features, (planar fractures and planar deformation features) in quartz grains, which formed when the rock underwent extreme shock pressures of between 7–35 GPa (1,000,000–5,100,000 psi).

[3] Since the impact, 7–8 km of rock has eroded away, leaving no visible depressions (compare, in contrast, Iso-Naakkima, Lumparn).