Northwest Seneca Station

The  is a part of the old metro system. The entrance is just north of Arefu on the opposite bank of the river. This collapsed metro station has a sewer tunnel that leads to Meresti Service Tunnel and eventually Meresti Metro Station, where The Family has their hideout.

Layout
The only accessible sections of the station are the restroom area and Murphy's Lab. The restroom area is inhabited by several Mole Rats, and there is a bench near a radioactive area where a skeletal corpse lies beside a bottle of Vodka and a dose of Psycho. Additionally, each restroom contains a First Aid Box and one of the sinks in mens' restroom is filled with Frag Grenades. There is also a hidden Plasma Grenade in between a Knife and Large Scorched Book, which can be found in the second stall to the right in the mens' bathroom as well. There is also a Nuka-Cola vending machine in the washroom area.

Murphy's Laboratory
Murphy's lab appears to be a converted maintenance room or office and is inhabited by two Ghouls; Murphy himself, and Barrett who Murphy describes as his "backup and assistant-- in case things get rough". There is also a manhole leading to the Meresti Metro Station in one of the rooms in the back-right corner of Murphy's Lab, surrounded by radioactive barrels. Speaking to Murphy can start the unmarked quest, Murphy's Bombing Run.

Grocer
Above ground and slightly to the east of the Seneca Station is a small, run down grocery store. Inside there are a few Radroaches that respawn, along with some random food goods, and a safe that may contain a Stealth Boy. If, for some reason, your lockpick skill is too low, there's also an Easy computer terminal you can hack that will unlock the safe.

Enclave Camp
After the The Waters of Life quest, an Enclave camp will appear on the highway overpass just west of the entrance to Northwest Seneca Station. The camp is populated by an Enclave Officer and two Enclave Soldiers, one of whom is equipped with Tesla Armor and a Missile Launcher. Curiously, the soldier with the Missile Launcher is friendly until you approach the camp and alert the two hostile Enclave. If you manage to stealth kill the two hostiles, the friendly soldier will remain friendly.

Notable Loot

 * In the men's bathroom in one of the stalls, the toilet is missing its tank. You should see the handle of a knife sticking out, and inside it and out of sight is a plasma grenade.

Related quests

 * Blood Ties
 * Murphy's Bombing Run

Appearances
This location appears only in Fallout 3.

Bugs

 * Outside of the station, there might be a random marker on your compass that is friendly or enemy. Upon approaching the marker, it disappears only to prove nothing's there. This may also happen around the far end of the bridge where Arefu is. [Confirmed PS3]
 * If Fawkes is your companion, sometimes he will attack Murphy and Barret, making it impossible to do Murphy's Sugar Bombing Run.