Picking Up the Trail

 is a Fallout 3 quest. It is also an Xbox 360 and PC achievement. It is achieved upon surviving Murder Pass and arriving at Vault 82.

After you get into the Citadel the Elder will be there to greet you, you will have a long boring conversation with him and he will tell you to go talk to the scientist "Scribe Rothchild" you will ask for the G.E.C.K. you will have to convince him but he will tell you to go to the A-Hall and the Pre-War Vault-Tech Terminal. Look in Vault Locations and go to Vault 87 and look at the Supplies. Then when you get a quest update you will to back to "Scribe Rothchild" and he will show you where to go.