Diamond City

This is one of the game's key locations and one of the safest areas in the Commonwealth. You'll first reach this location by following the main quest Jewel of the Commonwealth.

Mayor's Office

This is located in the highest level of the former stadium, accessible through the normal elevator by the city entrance or the maintenance gondola in the market. You can buy a house here for 2000 caps. You can talk to Geneva, the Mayor's secretary to get the housing permit.

Diamond City Market

• Super Salon: Allows you to modify your character's hairstyle.
• Dr. Sun's Clinic. Does facial reconstruction, has Chem station for use
• Eatery with protectron named Takahashi. Only sells noodles.
• Diamond City Surplus: Shop offering various items. It seems to be the only shop open for 24 hours since there are two characters manning the store. It also has an armor workbench you can use outside.
• Commonwealth Weaponry: Sells weapons and ammo. You can also find legendary weapons here like Big Boy and Old Faith. There's a weapon workbench that can be used for free outside.
• Home Plate: Your personal house in Diamond City with its own map marker. Has workbench inside, steamer trunk with ammo and weapon. Has a first aid box.

Publick Occurrences

This is Piper’s office. Has a mattress, unlocked terminal, ammo box.

Valentine Detective Agency

This is Nick Valentine’s office where you can recruit him as a companion and start a couple of sidequests by checking his pending case files.

Issue of Robco Fun on his desk. (Includes Zeta invaders game holotape)

Science! Room: Armor workbench, Cooking Station

Dr. Duff will ask you to bring parts of mutated creatures in the wasteland. You can haggle for cash.

Dugout Inn

This is the bar owned by the Bobrov brothers. You can buy drinks and rent a room inside. After leaving the place after your first visit, the quest “Confidence Man” will start.

Sheng's Purified Water

Ask for work, he'll ask you to clean the Water supply by picking up the underwater trash. Will offer for 100, but can be persuaded up to 200.

Schoolhouse

Behind the stairs in the ground floor, you'll find an issue of Live & Love, beside the bed.

You can talk to the robot named Edna and she'll ask you what love is about. Give her the “correct” idea of love and eventually, you'll encounter Edna and Zwick getting married.

Colonial Taphouse

This is located in the upper benches to the south of the market. Unlike the Dugout Inn which caters the general populace, this establishment only caters the city's wealthy residents.

Diamond City Radio

The radio station itself and the residence of the DJ, Travis.

Fallon's Basement

• Clothing shop run by Becky.
• Sells some unique armor pieces.
• Join the Railroad holotape on the dresser in the upper floor.