My ISP is owned by a company that resides in our neighboring country. I have noticed that when I do a traceroute to a server that I know is placed in the same country as I live, I can see some hops go through some servers with IP addresses registered in my neighboring country (according to RIPE database).
But I have heard that even if the IP is registered in another country, it necessarily does not mean that the traffic is really routed abroad to servers in that country.
How does that work in practice? How can I figure out which way my traffic really takes if I cannot trust traceroute?