Hej Ulrik,

På Penn Station er der såvel køreledning som sideskinne.

Men du har ret; det er Grand Central Terminal i New York City:

Grand Central Terminal, track #61, 16. august 2011 (nm).

Der er dog ikke tale om en postvogn, men om en særlig "rejsegodsvogn". Hvilken?

Bedste hilsener
Niels

Mon ikke dette er historien:
"Deep under Grand Central Terminal--in a location that is hidden away and can't be revealed here--there is a secret train station that dates to the 1930s. It was built to serve a single passenger: then-President Franklin Delano Roosevelt. The New York resident would often return to the city but didn't want anyone to see him in the wheelchair that his polio forced him to sit in. So this underground station was built to allow FDR to arrive secretly.

The president would arrive in a specially built train car that held FDR's specially designed armored Pierce-Arrow limousine. The train car had doors wide enough to allow the limo to drive straight off, and it would then drive through the doors of an extra-wide elevator. Finally, it would emerge in the ballroom of the Waldorf-Astoria hotel above, and no one would be the wiser about FDR's physical condition.

The secret station remained fully in operation until 1945, when FDR died. Today, the train car--seen here--remains under Grand Central and will likely stay there until the FDR museum can raise the funds to have it moved.

Read more: http://news.cnet.com/2300-11386_3-10004063-5.html#ixzz1WR3ZjJUr"