In general, a rural area or a countryside is a geographic area that is located outside towns and cities.
What is the meaning of country side?
1 : a rural area. 2 : the inhabitants of a countryside.
Why is it called countryside?
"section of a country, piece of land," mid-15c., perhaps literally "one side of a country," from country + side (n.); hence, "any tract of land having a natural unity" (1727). Meaning "inhabitants of a district or section" is from 1840.