Not quite. If you "display ip-network-map" you'll see which subnets belong to which region. If you display each region, you'll see what physical location it belongs to. Network Region 11,12,13, and 14 can all be part of location 11.
That's how an IP thing is tied to belonging to a physical location.
Then, if you look in those phones class of restriction - say, display cor 1 or 10 or whatever, you'll see a time of day chart. TOD Chart 1 = PGN1. TOD Chart 5 = PGN5
So, locations are you break out how to treat different dialed strings in different physical places.
Partition routing is how to break out different categories of user within the same loaction. Say, sales and support each have a PRI trunk. PGN1 hits route 1 for trunk 1 for sales. PGN2 hits route 2 for trunk 2 for support. That way if sales makes a ton of calls, they won't use the support group's trunks.
Now, a best practice was always to implement partition routing in PGN1 with TOD chart 1 for everyone when you build your PBX so if you ever needed to add another, you wouldn't have to edit every dialed string in ARS and map to "partition1" instead of "route 1". To say, if you print all your partition route indexes and you only ever have column 1 populated, it'd be a safe bet that the feature was never used but implemented in anticipation of it ever being required.