Level 16. Subpen 7 (2)

First secret: Head towards the edge where the water meets a raised platform. You'll spot two lampposts nearby. Look just below one of them for a small red lamp. From there, make your way to a rotating radar dish. Go around the corner, and you should see a wooden 'T' structure with two large banners and an old shield in the distance. Keep going around that area to find the secret.

For the second secret, you'll see a large naval vessel in the distance. Turn around and face West. You'll find some items hidden behind a set of crates.

Now, for secret number three: Use the crates from the previous secret. Jump onto them, then hop onto the crate next to a lamppost. From there, jump north onto a ledge to grab some ammo.

Secret four is located in the dry dock, specifically between two ships. One of these ships has a usable gun. You'll notice a door that's been blown open; look for a ripper heart inside the opening.

Finally, the fifth secret: East of a naval vessel that has a gun on it, you'll find a crate marked with the number '103'. Jump onto the platform, then make your way across the nearest crates until you discover a nuke.