Mail sent within 160 miles of it's destination should arrive at the destination within 2 to 3 days.
When you mail something it goes through several different sorting facilities before it reaches it's destination.
So the mail can go clear around your state before it's delivered.
Even mail that is to be delivered in the next town can go 3 to 4 towns which can be 100 miles or more away from the town you sent it from before being delivered.