Given the two options, I would go for the second...
However! What I would consider to be the best option is a third alternative. Something that combines information and instructions:
https://www.example.com/europe/sweden/ostergotland/linkoping/
This format gives the user a hint of what to write and expect. It's easy to understand that example.com/europe/
gives available countries in Europe and that
https://www.example.com/north-america/usa/california/san-francisco/
is the URL for viewing San Francisco.
Your options doesn't really tell the user what to expect. What region is 1? Which one is 2? Was it /1/2/3/4/
or /3/3/2/4/
for Paris?
I understand that using a text-ID for a city might not be feasible for you, but it's nonetheless the option I would recommend.
Some friendly reminders on the way:
Keep in mind that the use of regions are different depending on the
culture of the user. Americans might be used to enter information
about their state, while a Swede doesn't really put any significance
in the region and would prefer to write /europe/sweden/linkoping/
Remember to be kind to users who makes mistakes and writes
/europe/cannada/toronto/
Don't just tell them "Incorrect country
ID" but help them remedy their mistake by saying something like
"Cannada is not a country in Europe" or simply fix the error for them.