Peklynė is a legendary left slope of the Neris near Gulaičiai village. Over 30 m high, the slope is dug by ditches and horns in this place, so the remaining horns of the slope look like hills. The impression of the hills is enhanced by the rounded horn tops due to the fine sand that forms the surface.
The ditches and ravines are old enough. Their formation is related to the drainage of glacial lakes concentrated in these areas, which periodically took place during the lowering of the water level of the Neris River due to the intensive melting of the glacier.
In the vicinity of Peklynė hill (near Karagėliškės) in 1812. June 30 a part of Napoleon's army (the 3rd Corps of the French Army, commanded by Michel Neus) rose across the Neris. This corps marched from Kaunas on the banks of the Neris and had to clean and protect the left bank of the Neris from the Russians. After moving across the river, the soldiers drove further through Sudervė, Maišiagala, Giedraičius towards Vitebsk.