Yup..the location of your "ISPs main gateway that you exit and hit the public internet".
And with certain ISPs..,that gateway can randomly change across several locations "roughly in your region"...depending on load balancing and other factors.
If I do an IP lookup for my office...it's never in the town we're in...it's typically from several locations about 30 - 60 minutes north of us.
I'll periodically run traceroute just to see what's going on. When I was up in MA it was not uncommon to have 5-6 hops all through Spectrum nodes before I hit the Internet. Just did it hear and there's 8 hops through Spectrum/Charter land before it gets outside.
2 rrcs-96-10-228-81.midsouth.biz.rr.com (96.10.228.81) 1.524 ms 1.583 ms 1.092 ms
3 142-254-207-221.inf.spectrum.com (142.254.207.221) 14.812 ms 18.831 ms 13.524 ms
4 lag-62.rlgknc6701h.netops.charter.com (174.111.105.240) 23.371 ms 37.287 ms 31.234 ms
5 lag-40.drhmncev02r.netops.charter.com (24.25.63.12) 15.301 ms 17.928 ms 13.847 ms
6 lag-31.rcr01drhmncev.netops.charter.com (24.93.64.184) 15.107 ms 18.827 ms 15.103 ms
7 lag-415.asbnva1611w-bcr00.netops.charter.com (107.14.18.106) 13.165 ms
lag-12.asbnva1611w-bcr00.netops.charter.com (66.109.10.176) 22.351 ms
lag-15.asbnva1611w-bcr00.netops.charter.com (66.109.6.80) 21.137 ms
Of course that'll vary based on the chosen end point. Several years ago I was looking at proxy servers. A common way to disguise the source IP. Not surprising all the Chinese ones went through a Northern VA located IP owned by a major Federal contractor.
For years my AT&T WLAN exited somewhere in Oklahoma, going through a half dozen or so private IP nodes before hitting the wild.