The 1950s marked the beginning of a colossal secret tunnel system that linked the White House to several other key points in and around the city. Engineered as a plan to evacuate the president in case of an emergency (it was the height of the Cold War, after all), this underground network connected the White House to the Eisenhower Executive Office building next door, the bunker under the Blair House, a hotel near the White House, the U.S. Capitol, Pentagon, and other federal buildings. Plus, a hot ticket on a secret train that runs between D.C.’s Union Station and Mt. Weather.

http://www.msn.com/en-us/news/politics/sixteen-secrets-of-the-white-house/ar-BBpaIqF?ocid=spartandhp

Tell us next about the secret tunnel that lets submarines sail from the Pacific into Lake Walker in the Nevada desert. There's no limit to the nonsense that goofballs will make up.

The semi-mythical train to Mt. Weather is (was) not underground and the article didn't claim it to be a tunnel. It's not really secret and not a regular scheduled run for that matter.

There are tunnels under most of the buildings. With respect to the Executive Office Building it isn't so much a tunnel but interconnected basements. The White house itself is much too small for all the offices and infrastructure for communications and support, so most of the area below the surface of the grounds has basement levels which connect to the Executive Office building next door. These are much more extensive than the basements and tunnels under the congressional office buildings.

Not all the other tunnels are regularly used. It was proposed for Metro to expand the "secret" subways that was too costly and never came to fruition. It is usually considered faster and safer for the President to travel above ground to local destinations in the area.

Treasury and the Treasury Annex across PA Avenue are connected by a pedestrian tunnel. Various federal offices in the area are connected by "steam tunnels" as that's how they were and in some cases are heated. The grates you may see homeless people sleeping on in the winter are typically the ventilation shafts for those tunnels. Because of the steam being piped through them, the tunnels are warm and the air coming up through the grates is as well. Nothing mysterious about any of it at all.

mole Wrote:
-------------------------------------------------------
> The semi-mythical train to Mt. Weather is (was)
> not underground and the article didn't claim it to
> be a tunnel. It's not really secret and not a
> regular scheduled run for that matter.
>
> There are tunnels under most of the buildings.
> With respect to the Executive Office Building it
> isn't so much a tunnel but interconnected
> basements. The White house itself is much too
> small for all the offices and infrastructure for
> communications and support, so most of the area
> below the surface of the grounds has basement
> levels which connect to the Executive Office
> building next door. These are much more extensive
> than the basements and tunnels under the
> congressional office buildings.
>
> Not all the other tunnels are regularly used. It
> was proposed for Metro to expand the "secret"
> subways that was too costly and never came to
> fruition. It is usually considered faster and
> safer for the President to travel above ground to
> local destinations in the area.


Of course this is all true.
The parody of Whitehouse.gov site says it true!
You can even eat in the White House.

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

I believe the MSN story.

So do I, because it's true.

Source: I was a screenwriter on xxx state of the union (2005)

The underground complex around the White House is huge. It's not really secret since anyone with some kind of official business can get in. The underground complex around the Capitol is mostly open to the public and also very large.