This level contains 6 secrets in total. The order of secrets 3, 4 and 5 can likely be different.
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Achievement: Cute Trains
Waste three minutes watching the model railway.
Next to a poster of a horse (secret #2) there is door to a room with model railway, you can’t miss it. Start the trains and just observe it for 3 minutes.
Achievement location is the green dot on the map.
Hidden backpack: Right after your surface for the first time using the stairs, there is a secret area on the left at the block of flats, right below the first line of windows from the left (windows, not balconies). Interact with it to find a backpack with ammunition.
Secret garage basement: The middle garage has a car parked inside. There is a hidden area under the car. Destroy the car and then the metal entrance to the basement.
Secret bathroom: Behind a poster with a horse, dated 1986, there is a crack in the wall. Break through to find a secret area with 5 koruna and a washing machine.
Elevator secret area: After you open door to elevator shaft, you can notice a different looking square above the elevator counterweight. You have to destroy the electric panel for the counterweight go slightly up so you can reach the spot.
Secret room in the block: In the area with general store and phone booth, there is a single balcony that is accessible. It leads to a flat with a single kejdovec enemy and 1 koruna coid. To get there you need to reach the roof of one of the blocks again and then jump from there to the balcony.
Construction site hidden spot: Right as you enter the construction site area, there is a lamp on the left side. Near this lamp, in the corner you can find an interactable wall. You will find some grenades there.