The first episode of Community describes Greendale Community College as being "three blocks from your home," and this phrase carries a deeper meaning that sets up the show's premise. Community never explains the meaning of this line after it appears over the very first establishing shot of the series. However, Community's Greendale location actually has a lot of meaning, and there is a more interesting backstory behind the "three blocks" line.

https://screenrant.com/why-community-greendale-three-blocks-from-home/