Coaster harbour
From Cantr II Wiki
The coaster harbour is a freestanding building that must be built within a town's main area. It can have internal rooms. However, its prime purpose is to allow ships to dock that usually can't; any ship/boat can dock to a harbour, even if they can't dock to the town's beach. The building can be locked, but boats may still dock.
The harbour can only be built when an area has access to the sea. If the area is on a lake, a landing-stage is required.
Construction
Object: Coaster Harbour
Days needed: 20
Raw materials needed: 20000 grams of stone
10000 grams of wood
500 grams of iron
Objects: none
Tools needed: trowel
Capacity
People: 20
Weight: 2000000 grams