RUST LOGIC
GREEN TIER

Verified for the August 2026 patch · updated Aug 20, 2026

Harbor (Small) Puzzle Guide — Green Card Route

Small Harbor needs a green keycard and 1 electric fuse. Reward: a blue keycard. Flip the exterior switch, fuse the building, then hit the hangar's back-right green door.

Difficulty: easy · time on-site: 3–5 min · by RustLogic Staff

Bring exactly this

  • Green card ×1
  • Electric fuse ×1
Harbor (Small) — puzzle circuit
S Exterior switch F Fuse box inside Hangar green read… Blue card + crate

The small Harbor circuit runs backwards compared to most greens — the switch is outside. Learn the order once and this becomes your fastest blue card on coastal maps.

Before you go

Green keycard + one electric fuse. No rads, no NPCs.

The route

  1. Flip the exterior switch first. It’s on the outside of a building in the yard — arm the circuit before you go interior.
  2. Fuse the building. Head inside and place your fuse in the fuse box. With switch + fuse both done, the hangar reader is live.
  3. Hangar, back-right. Enter the main hangar and move to the back-right corner — the green reader sits on the door there.
  4. Swipe and loot. Inside: a crate and the blue keycard.

After the run

Hit the recycler with your dock components, then plan the blue spend: Water Treatment or Train Yard each turn that blue card into a red one for a single fuse.

Harbor (Small) — quick answers

What do I need for the small Harbor puzzle?
A green keycard and one electric fuse. No radiation protection required.
Where is the green door at small Harbor?
At the back-right of the main hangar. Power it via the exterior switch and the fuse box inside the adjacent building first.
Small Harbor or large Harbor — which is faster?
Small Harbor is usually the faster card run; large Harbor has more loot and the Cargo Ship dock. Same requirements and same blue-card reward either way.