Žvelsa is a river in western Lithuania, a left tributary of the Minija River, stretching 38 km long with a 144 km² basin area.

In the Lapių region, Žvelsa flows through rugged terrain and forested areas, with numerous exposed cliffs and hillforts along its banks. The river’s most accessible and developed sections for recreational use are near Lapių village, where private homesteads and cultural sites, such as (D. Holliday’s homestead, Lapių Hillfort, and Nightingale Valley), enhance the experience. However, more remote sections of the river remain untouched and preserve their natural character.

During summer, Žvelsa flows calmly, but in autumn, when water levels rise, it becomes highly active, resembling a mountain river. The upper course of the Žvelsa River has a steep gradient, with strong currents rushing through fallen trees, rocks, and beaver dams. The canoeing route extends up to 14 km, and under these extreme conditions, paddling even a short distance requires significantly more effort than on calm waters.

As water levels rise in autumn, the Žvelsa canoeing season begins. If the river does not freeze over and weather conditions permit, paddling continues through winter and into April. Žvelsa is considered one of the best rivers in Lithuania for extreme canoeing.