The location consists of two skyscrapers (collectively labeled "ruined skyscraper" on the local map) connected internally by a walkway on the eleventh floor. It is the scene of a battle between Gunners and super mutants. The interior has been devastated.
There are two entrances to the buildings. The eastern entrance is found by heading west then north from the southern end of Postal Square to reach a fire escape on the right diagonally across the street from a bus stop; the escape leads up to the eastern skyscraper entrance into the sixth floor. The western entrance is found by continuing west behind the left side of the bus stop then turning south into the narrow alley just past the wrecked bus and across the street from the Water Street apartments to reach a set of two fire escapes; the escapes lead to a button-activated elevator on the roof which ascends to the fallen skybridge hanging from the west side of the western skyscraper, which leads to the western skyscraper entrance into the twenty-first floor.
The sixth floor is entirely controlled by Gunners. The elevator to the southeast connects to the eleventh floor, while the door to the northeast exits to the Financial District (serving as the eastern entrance described above). It is on this floor that the cache for the Jackpot mission can be found.
The eleventh floor is filled with super mutants fighting Gunners. The elevator to the east leads down to the sixth floor, while the elevator to the west leads up to the twenty-first floor.
The body of a Gunner is on the couch ahead when entering from the elevator, with a second body behind the desk on the right, and a third body in the small room at the top of the stairs near a lone super mutant. The player character can exit to the fallen skybridge (serving as the western entrance described above), or through the elevator down to the eleventh floor.
- A Stealth Boy - In the Jackpot cache on the sixth floor, on top of a shelf.
- Jackpot: Ruined Skyscraper: P.A.M. tasks the Sole Survivor with unlocking a hidden DIA cache containing military-grade gear and supplies that the Railroad is in dire need of.
- There is a skull in the toilet on the sixth floor just before the exit, with bandage scissors and a hairbrush on the rim of the bowl.
- Loot and enemies will respawn for the quest Jackpot.
Pinnacle Highrise appears only in Fallout 4.