STOLLEN MEANS TUNNEL, DUMB, MINE

https://www.collinsdictionary.com/dictionary/german-english/stollen

https://www.washingtonpost.com/politics/2020/06/01/what-we-know-about-white-houses-secret-bunkers-tunnels/

Obama enlarged this tunnel system underneath the White House - Why?

https://whitehouse.gov1.info/tunnel/

West Wing Construction: A New White House Bunker? - In 2010, tall fences went up outside the West Wing of the White House and a massive construction project was underway. Officially, the construction project was described as a much-needed infrastructure systems replacement. The massive scope of the project, described as a "sprawling, multistory structure whose underground assembly required truckloads of heavy-duty concrete and steel beams", led to many questions and conspiracy theories. Was this a new presidential command center housing its own massive communications data center? One official stated off the record "It is security-related construction."

There was some speculation that this temporary building housed a data center with communications equipment. The building was removed at some point during the West Wing construction project perhaps with its equipment relocated below ground.

https://archive.ph/KDrc0#selection-635.0-649.286

Temporary Relocation of the Oval Office Postponed Much of the West Wing of the White House, including the Oval Office, was going to be relocated to the Eisenhower Executive Office Building next door to allow for the installation of the wiring, elevators, and secret entrances to the new command center below them. Due to public curiosity and concerns over cost, the relocation plan was postponed until the next administration, which has unexpectedly worked out perfectly since incoming President-Elect Trump probably won't be spending much time in there anyways.

It is imperative that the President be able to safely evacuate to the command bunker below without having to leave the Oval Office. The existing trap door under the President's desk leading down to the Secret Service "Horsepower" command post in the basement of the West Wing will be modified to allow presidential passage directly to the new underground command bunker.

A second Oval Office will be built in the south end of the Eisenhower Executive Office Building. The Secret Service is working closely with the construction crews providing top secret security specifications for the windows, walls, and access points for the President's new workplace.

https://www.popsci.com/story/military/tunnels-capitol-white-house-washington/

https://www.covertconcepts.com/concealed-passages-white-house/

https://www.military.com/daily-news/2018/06/24/army-spending-half-billion-train-troops-fight-underground.html

An assessment last year estimates that there are about 10,000 large-scale underground military facilities around the world that are intended to serve as subterranean cities, an Army source, who is not cleared to talk to the press, told Military.com.

The Army's Asymmetric Warfare Group -- an outfit often tasked with looking ahead to identify future threats -- told U.S. military leaders that special operations forces will not be able to deal with the subterranean problem alone and that large numbers of conventional forces must be trained and equipped to fight underground, the source said.

https://www.thedrive.com/the-war-zone/33003/the-pentagons-plan-to-build-a-secret-super-command-bunker-3500-feet-under-washington-d-c

UNDERGROUND BASES

(Chapter 2, page 19)