The Grestin border checkpoint is located between West Grestin in Kolechia and East Grestin in Arstotzka. This is where all the gameplay will occur. The border is opened on Day 1 after the war between Arstotzka and Kolechia resulting in the division of Grestin. and the newspaper then states that "Families are to be re-united." The inspector's booth is located in this location along with the line of entrants trying to get inside East Grestin and thus Arstotzka, the guard post (north from the booth) and a road (on the right).
The checkpoint is frequently attacked by terrorists, as a reference to Sergiu (survived to day 22), more actions in the checkpoint than in Kolechia. Sometimes, the Inspector also witnesses these attacks himself and at several points, is tasked to handle them.