"Undulating hills" refers to a landscape where the land is shaped like gentle waves or curves. It means the hills have a smooth and wavy appearance, similar to the way in which water moves in a wave-like motion. Full definition
The Natal Midlands conjure up a picture of green undulating hills, clean air, country villages, pubs, a collection of artists, waterfalls, forests and the foothills of the Drakensberg. (blog.sa-venues.com)
«The landscape becomes much more severe as well, with undulating hills and red volcanic soils,» says Horvath, who commutes weekly by plane to check on vines and wines. (winemag.com)
We drive north through undulating hills; the dry countryside looks like the foothills of the Sierras in southern California. (discovermagazine.com)