Pass Value to another page.

Hey everyone, I'm creating kind of a directory by city and i have a starting page where i have all the cities available as links so when people click in a specific city, for exemple "city1" it leads to a second page where the program is suposed to identify that this is "city1" page and from now one every search on the database shoul look only for city1 records. So how do i pass this info from the starting page to de second page and store it and make it available so i can use it in the query for the database?!

Thank You for your time.
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