People from all over the country are mixed here to the max (但是to the max是个美国俚语,在这种语境不合适),including the locals.This place can become the location for multi-level multi-cultural exchange and understanding.
The mixing /gathering /accumulation/ assembly of people from all districts/ areas of the country - locals included of course - can turn this place into a location for maximum exchange and understanding among diverse levels and cultures.
People from all over the country,including the locals,mix here,making it a place /providing a location for maximum exchange and understanding among diverse levels and cultures.
This place enables people...to (meet and) mix and to achieve maximum understanding among different levels and cultures.