Latvia is a sparsely inhabited lowland country. The population density is 34 people per square kilometer, but most of that is concentrated around Riga.
As such, the remainder of Latvia consists of vast areas of quite pristine forests, rivers, and lakes with a town here and there.
The most typical natural sights have been amalgamated into National Parks. The most famous among those is Gauja National Park around Sigulda, easily accessible from Riga. It surrounds the valley of the longest river that starts and ends in Latvia. In addition to landscapes it the park offers Crusader castles and active entertainment.
Less easily accessible other national parks include the one around Lake Raznas in Latgale (a region famous for its numerous lakes) as well as Slītere National Park near Kolka Peninsula that is the end of Western Latvia. In addition to forests (where beasts live), it boasts a unique indigenous Liv culture.
Gulbene-Alūksne area is also famous for its natural views.