This Destiny 2 Trostland Lost Sectors page will explain where to find all the mini-dungeons within that area of the EDZ / Earth Patrol space.
If you want more information on how to find Lost Sectors and the rewards they offer, our Lost Sectors locations page can help.
Destiny 2 Trostland Lost Sectors
The three Lost Sectors in Trostland are:
Location: Head to the back of the church where you found Devrim. On the ground floor, you'll find the symbol below.
Strategy: A basement door will open to your right. Follow it down then follow the path as it weaves through corridors to your left.
You'll eventually come to a room filled with patrolling Fallen. Take them down, go through the doorway to your left, take out the Fallen at the bottom, then turn right.
Turn right again and you'll find a room filled with Fallen and a boss (Skexis, Outcast Captain). Use your Super and your power weapon to wear him down and collect your rewards.
Widow's Walk location
Location: With the front of the church directly in front of you, head down the street to its left and you'll find the symbol below outside a shop.
When you go into the doorway, take a right and follow the corridor round.
Strategy: The doorway to the dungeon is inside (see screenshot), follow the passage way, down the stairs and into a large open area with a piece of machinery in the middle. Kill enough Fallen and the boss (Mazan, Lost Captain) will make himself known. Use the cover provided by the open shops to your advantage and take out the sniper at the far end of the area to reduce your grief.
For Season of Plunder, we have the Sails of the Shipstealer quest, Treasure Coordinates and Map Fragments, Cryptic Quatrains and weapons such as the Quicksilver Storm and Taipan 4FR. Meanwhile, there's the arrival of King's Fall and King's Fall challenges, plus weapons including Doom of Chelchis and Touch of Malice. For The Witch Queen, learn how to get Exotics including Dead Messenger and Parasite.
Terminus East location
Location: To find this location, head to the back of the church and turn right. You should see the symbol just outside a ruined subway station entrance.
Strategy: Slide under the doorway shown in the screenshot, climb down the sinkhole and follow the tunnels until you reach a ruined platform.
Take out the first Fallen, then focus on the snipers to your right (they'll be on an elevated platform).
The boss (Kalsis, Sunless Captain) will hold off in the rear. Try and mop up the other fallen before concentrating fire on him.