The Underground

The Underground, a sprawling network of tunnels and hidden passages beneath Boston and New York, serves as a vital fast-travel system and a source of unique collectibles in Assassin's Creed III. Unlocking these entrances, known as Underground Entrances, is crucial for efficient traversal and completing the "Underground" side quest. Each entrance requires a specific interaction, often involving a bit of parkour or puzzle-solving, to reveal its secrets.

Unlocking Underground Entrances

There are a total of 11 Underground Entrances to discover and unlock across Boston and New York. Each entrance, once found, will be marked on your map. To activate them for fast travel, you must locate and interact with a specific mechanism within the immediate vicinity of the entrance. This often involves finding a hidden door, a movable object, or a pressure plate. Successfully activating an entrance will reveal the entire section of the Underground connected to it on your map.

Boston Underground Entrances

Boston Common: Located near the southern edge of Boston Common. Look for a small, dilapidated shack. The entrance is a hidden door on its side.
North End: Found within the North End district, close to the docks. Search for a series of crates and barrels; the entrance is concealed behind them.
Central Boston (South): Situated in the southern part of Central Boston, near the harbor. Keep an eye out for a small, brick building with a boarded-up window. The entrance is behind the boards.
Central Boston (North): In the northern section of Central Boston, near the Old North Church. Look for a narrow alleyway with a wooden fence. The entrance is hidden behind the fence.
Beacon Hill: On Beacon Hill, near the opulent mansions. The entrance is a well-hidden grate on the side of a building, requiring some careful climbing to reach.
South Boston: In the southern district, close to the border with the Frontier. Search for a small, abandoned house. The entrance is a cellar door.

New York Underground Entrances

North New York: Located in the northern part of New York, near the border with the Frontier. Look for a large, ruined building. The entrance is a collapsed section of its foundation.
West New York: In the western district, near the river. Search for a series of wooden scaffolding. The entrance is a hidden door beneath them.
East New York: Situated in the eastern part of New York, close to the docks. Keep an eye out for a small, brick warehouse. The entrance is a hidden passage behind some crates.
South New York: In the southern district, near the financial hub. Look for a large, ornate building. The entrance is a hidden grate in its basement.
Trinity Church: Directly beneath Trinity Church. This entrance is typically unlocked as part of a main story mission or a specific side quest, rather than being a standalone discovery.

Navigating the Underground

Once inside the Underground, you'll find a labyrinthine network of tunnels, sewers, and hidden chambers. Your map will display the unlocked sections, making navigation easier. The Underground is not just for fast travel; it also holds valuable collectibles and offers unique opportunities for stealth and evasion.

Underground Challenges & Collectibles

Within the Underground, you'll encounter two primary types of collectibles:

Underground Maps: These maps, often found in chests or on tables, reveal further sections of the Underground on your main map, making it easier to locate other entrances and collectibles.
Underground Chests: These chests contain various rewards, including money, crafting ingredients, and sometimes even unique weapon upgrades. They are often hidden in secluded corners or behind environmental puzzles.

Additionally, the Underground often features environmental puzzles or obstacles that require specific actions to overcome. These might include:

Movable Crates: Push or pull crates to open new paths or reach higher ledges.
Breakable Walls: Use your hidden blade or a weapon to destroy weak sections of walls, revealing hidden passages.
Pressure Plates: Stand on pressure plates to activate mechanisms, such as opening doors or lowering platforms.
Climbing Sections: Utilize Connor's parkour abilities to navigate vertical shafts and reach inaccessible areas.

Strategy for Completion

To efficiently complete the "Underground" side quest and unlock all fast travel points, follow these steps:

Prioritize Map Acquisition: As you explore the surface, keep an eye out for any Underground Entrances. Once inside, prioritize finding any Underground Maps. These will reveal more of the network and guide you to other entrances.
Systematic Exploration: Once you've entered a section of the Underground, try to explore it systematically. Follow the main pathways first, then backtrack to check for hidden alcoves or branching tunnels.
Utilize Eagle Vision: Eagle Vision is invaluable in the Underground. It will highlight interactive objects, hidden passages, and the locations of chests, making your search much more efficient.
Be Prepared for Combat: While not heavily guarded, you may occasionally encounter small groups of Redcoats or other enemies within the Underground. Be prepared for stealth takedowns or direct combat if necessary.
Fast Travel Between Entrances: Once you've unlocked multiple entrances, use the fast travel system to quickly move between different sections of the Underground, saving time and making it easier to track down remaining collectibles.