For my homebrew campaign.

Elderpine keep is a gigantic castle with multiple levels/tiers. Inhabitants within the walls: approx. 100.000 before the fire. Approx 80.000 after the fire.

City overview map: https://inkarnate.com/m/A1kRqd--elderpine-keep/

Tier 0: cave complex with below ground harbor

Tier 1: commonfolk/traders/craftsmen (https://inkarnate.com/m/L5xv1L--tier-1-elderpine-keep/)

Tier 2: military and combat training grounds (https://inkarnate.com/m/7978yj--elderpine-keep-tier-2/)

Tier 3: Libraries and universities (https://inkarnate.com/m/E5ZEX2-elderpine-keep-tier-3/)

Tier 4: Nobility

Tier 5: Royalty

The lowest tier of the keep has little inhabitants. It is mostly used as a harbor. The entrance to the harbor is a cove which you can enter from the open sea. Once you sail through the rocky arches, you enter the Kraken's Nest Cove. This cove derives its name from a great kraken that made its home here millinia ago. Long dead, but the name still stands.

The keep is on elivated land. So there was little oppertunity to create a harbor nearby, since the cliffs stretch out for miles. For this reason, the rulers of old started to dig out a tunnel complex beneath the castle which they connected to the cove. This complex got turned into a harbor.

After sailing though the cove there are three ways you can go, each with its own level of restrictions and admittance.

The Commoner's Harbor has acces and supplies Tier 1.

The Millitary Port has acces and supplies Tier 2.

The Kings Haven has acces and supplies Tier 4 & 5.