Hidden throughout New York are 35 Underground caches just waiting to be discovered. You'll get a Tech Point for each one that you find and can use these to upgrade gadgets, craft mods and even unlock new suits for Miles to wear as he swings his way across the city. You'll also get the "Salvager" trophy for collecting them all.

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Before you can start tracking them down though, you'll first need to complete the main story mission "Harlem Trains Out of Service". After doing so, you'll be free to collect the other 34 in any order you like. In order to find them, you'll need to head to the locations marked on the map and then activate the compass using R3 to pinpoint their exact locations.

Underground Cache #1 - Midtown

Underground Cache #1 - Midtown in Spider-Man Miles Morales

Miles will find the first cache about half way through the story mission "Harlem Trains Out of Service". It can't be missed, so just make your way through the mission as instructed.

Reward(s): 1 Tech Part

Underground Cache #2 - Central Park

Underground Cache #2 - Central Park in Spider-Man Miles Morales

Head to the northern area of the park and look for the small structure with the large flagpole. You'll find the cache beneath the American flag near some cardboard boxes.

Reward(s): 50XP + 1 Tech Part

Underground Cache #3 - Central Park

Underground Cache #3 - Central Park in Spider-Man Miles Morales

Make your way to the fountain and then follow the compass to a breakable wall. You'll find the cache in the center of this newly accessible structure next to some garbage bags.

Reward(s): 50XP + 1 Tech Part

Underground Cache #4 - Chinatown

Underground Cache #4 - Chinatown in Spider-Man Miles Morales

The marker will lead you to a Roxxon gas station with a couple of garages and a snack shop. Use L1 and R1 to pull the gear above the left hand garage and then quickly fire some web at it to hold it open.

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You'll then need to crawl under the car and drop down the hatch into the lab below. From here, head through the vent above the door to your left and you'll see the cache directly in front of you once you emerge on the other side.

Reward(s): 50XP + 1 Tech Part

Underground Cache #5 - Chinatown

Underground Cache #5 - Chinatown in Spider-Man Miles Morales

About half way up the building there is some computer equipment covered by a white pavilion. The cache is to the left of the monitors and is quite hard to miss.

Reward(s): 50XP + 1 Tech Part

Underground Cache #6 - Chinatown

Underground Cache #6 - Chinatown in Spider-Man Miles Morales

The cache is hidden on the third story of a multi-layered parking structure slap-bang in the center of Chinatown.

Reward(s): 50XP + 1 Tech Part

Underground Cache #7 - Chinatown

Underground Cache #7 - Chinatown in Spider-Man Miles Morales

Make your way to the top of the tower block with the white pavilion on top and you'll find the cache right next to one of the building's stairwells.

Reward(s): 50XP + 1 Tech Part

Underground Cache #8 - Financial District

Underground Cache #8 - Financial District in Spider-Man Miles Morales

Follow the marker to the gas station and then open up the garage on the right. Travel through the air vent and then look for the generator. You'll need to charge it up and then connect it to the pilon next to the door near where you entered. After it unlocks, you'll be able to get to the cache.

Reward(s): 50XP + 1 Tech Part

Underground Cache #9 - Financial District

Underground Cache #9 - Financial District in Spider-Man Miles Morales

The cache is on a rooftop hidden beneath some stairs. Before you can reach it though, you'll first need to pull the green dumpster out of the way by holding L1 and R1. Just make sure to jump straight after doing so to avoid being crushed against the wall.

Reward(s): 50XP + 1 Tech Part

Underground Cache #10 - Financial District

Underground Cache #10 - Financial District in Spider-Man Miles Morales

Swing around the back of the building and you'll find a couple of boat docks. The cache is against the wall on the left in the one on the right hand side.

Reward(s): 50XP + 1 Tech Part

Underground Cache #11 - Financial District

Underground Cache #11 - Financial District in Spider-Man Miles Morales

Look for the green shipping container with the Underground logo painted on the front of it and then use L1 and R1 to pull it open. Follow the tunnel around and you'll eventually make it to the cache.

Reward(s): 50XP + 1 Tech Part

Underground Cache #12 - Financial District

Underground Cache #12 - Financial District in Spider-Man Miles Morales

The cache is on a rooftop near some air-conditioning units. You'll need to break the wooden crate with the Underground logo on it in order to gain access to it though.

Reward(s): 50XP + 1 Tech Part

Underground Cache #13 - Greenwich

Underground Cache #13 - Greenwich in Spider-Man Miles Morales

Find the gas station and then use your webbing to open up the garage on the left. As always, you'll need to shoot it immediately afterwards to hold it open. The cache will be right in front of you.

Reward(s): 50XP + 1 Tech Part

Underground Cache #14 - Greenwich

Underground Cache #14 - Greenwich in Spider-Man Miles Morales

Make your way to the rooftop and then drop down the old elevator shaft. Take a hard right as soon as you land and climb over the metal fence. You'll find the cache on the other side next to some server equipment.

Reward(s): 50XP + 1 Tech Part

Underground Cache #15 - Greenwich

Underground Cache #15 - Greenwich in Spider-Man Miles Morales

Head inside the Consolidated Shipping depot and destroy the three wooden crates. You'll find the cache to your left in front of some rolling shutters with the Underground logo painted on them

Reward(s): 50XP + 1 Tech Part

Underground Cache #16 - Greenwich

Underground Cache #16 - Greenwich in Spider-Man Miles Morales

Near the top of the building you'll find a metal cage next to some solar panels. The cache is inside the cage, but you'll first need to yank the door off with L1 and R1 before you can get your hands on it.

Reward(s): 50XP + 1 Tech Part

Underground Cache #17 - Harlem

Underground Cache #17 - Harlem in Spider-Man Miles Morales

Head to the construction zone and find the grey double doors. You'll be able to use your web to pull them open and can then find the cache inside the building opposite the door that you entered from.

Reward(s): 50XP + 1 Tech Part

Underground Cache #18 - Harlem

Underground Cache #18 - Harlem in Spider-Man Miles Morales

Get on top of the shipping containers and look for a gap in the stack. Drop down into it and you'll find the cache inside a blue container.

Reward(s): 50XP + 1 Tech Part

Underground Cache #19 - Harlem

Underground Cache #19 - Harlem in Spider-Man Miles Morales

Follow the marker to the gas station and open up the garage on the right, being sure to fire some web to lock the gear in place. The cache is against the back wall of the garage

Reward(s): 50XP + 1 Tech Part

Underground Cache #20 - Hell's Kitchen

Underground Cache #20 - Hell's Kitchen in Spider-Man Miles Morales

Head to the gas station and use your web to open up the garage on the left. Next, you'll need to crawl through the air vent whilst also stopping the fan with your web. After you drop down into the lab, take out the Roxxon employee and power the generator that he was working on to open the door.

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Straight after walking through it, you should see an air vent directly in front of you. Climb in and then take a right followed by two lefts. Stop another fan, turn left one more time and then drop down into the room below to find the cache.

Reward(s): 50XP + 1 Tech Part

Underground Cache #21 - Hell's Kitchen

Underground Cache #21 - Hell's Kitchen in Spider-Man Miles Morales

This one's sat right in front of the revolving doors at the entrance to Fisk Tower. In order to get to it though, you'll first need to climb or swing over the metal fence.

Reward(s): 50XP + 1 Tech Part

Underground Cache #22 - Hell's Kitchen

Underground Cache #22 - Hell's Kitchen in Spider-Man Miles Morales

Follow the waterfront around and you'll find the cache in a fenced-off area beneath the base of a small crane.

Reward(s): 50XP + 1 Tech Part

Underground Cache #23 - Hell's Kitchen

Underground Cache #23 - Hell's Kitchen in Spider-Man Miles Morales

Make your way to the top of the building and destroy the two wooden crates to gain access to the metal cage. The cache is directly in front of you next to some computer monitors.

Reward(s): 50XP + 1 Tech Part

Underground Cache #24 - Midtown

Underground Cache #24 - Midtown in Spider-Man Miles Morales

Climb up to the roof and over the metal fence. The cache is under a tarp near some flaming trashcans.

Reward(s): 50XP + 1 Tech Part

Underground Cache #25 - Midtown

Underground Cache #25 - Midtown in Spider-Man Miles Morales

Find the Ellie Jude Hotel and travel around it at street level until you see some metal scaffolding. Hold L1 and R1 to pull it down and you'll find the cache to the left of the newly accessible area.

Reward(s): 50XP + 1 Tech Part

Underground Cache #26 - Midtown

Underground Cache #26 - Midtown in Spider-Man Miles Morales

Head up to the roof of the building and drop down onto the lowest level if you're not already there. The cache is behind a wooden fence.

Reward(s): 50XP + 1 Tech Part

Underground Cache #27 - Midtown

Underground Cache #27 - Midtown in Spider-Man Miles Morales

Just below the roof of the tall glass building there's a small balcony area with some potted plants and construction equipment. The cache is next to the railings overlooking the city.

Reward(s): 50XP + 1 Tech Part

Underground Cache #28 - Upper East Side

Underground Cache #28 - Upper East Side in Spider-Man Miles Morales

The cache is on top of the old, church-like building surrounded by cardboard boxes.

Reward(s): 50XP + 1 Tech Part

Underground Cache #29 - Upper East Side

Underground Cache #29 - Upper East Side in Spider-Man Miles Morales

Look for the C-shaped building with the two flags that's facing Central Park. To the left of the entrance you should see some construction work. Use L1 and R1 to pull down the scaffolding and then take a left after going through the archway to find the cache.

Reward(s): 50XP + 1 Tech Part

Underground Cache #30 - Upper East Side

Underground Cache #30 - Upper East Side in Spider-Man Miles Morales

Head to the courtyard and you'll find a large green skip hidden behind a piece of destructible plywood with the Underground logo painted on it. Use L1 and R1 to pull the skip out of the way and you'll now have access to the cache.

Reward(s): 50XP + 1 Tech Part

Underground Cache #31 - Upper East Side

Underground Cache #31 - Upper East Side in Spider-Man Miles Morales

Drop down into the large courtyard with the fountain in the center and look for a huge piece of plywood with the Underground logo painted on it. As you might have already guessed, it's destructible, so break it down and you'll find the cache slightly to your right.

Reward(s): 50XP + 1 Tech Part

Underground Cache #32 - Upper East Side

Underground Cache #32 - Upper East Side in Spider-Man Miles Morales

Make your way to the gas station and use your web to open the garage on the left hand side. Doing so will cause a tank to come out which you'll need to destroy by pulling off the turret with your web. After you've taken care of it, return to the garage to collect the cache.

Reward(s): 50XP + 1 Tech Part

Underground Cache #33 - Upper West Side

Underground Cache #33 - Upper West Side in Spider-Man Miles Morales

Head to the roof of the building and you'll find a pavilion with some computer equipment inside. The cache is near the entrance next to some sandbags.

Reward(s): 50XP + 1 Tech Part

Underground Cache #34 - Upper West Side

Underground Cache #34 - Upper West Side in Spider-Man Miles Morales

Make your way up to the roof and look for the large sheet of plywood with the Underground logo painted on it. The cache is right in front of it between some stacks of concrete mix.

Reward(s): 50XP + 1 Tech Part

Underground Cache #35 - Upper West Side

Underground Cache #35 - Upper West Side in Spider-Man Miles Morales

Find the building with the construction work taking place on the roof and enter the metal cage. To the right of it, there's a destructible wall that's hiding the cache.

Reward(s): 50XP + 1 Tech Part

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