Here's their map: https://locations.wafflehouse.com
Waffle House started just outside of Atlanta, and you can still see that. In other big cities they seem to stay outside of the core - I suspect they don't want to have locations without parking. (But off the top of my head I can name two Atlanta-area Waffle Houses that don't have their own parking, namely the one right off Centennial Olympic Park and the one in downtown Decatur.)