A friend of mine from Boston told me a fun story once:
Once upon a time …
The Massachusetts Bay Transportation Authority wanted to extend the Ⓣ Red Line, and wanted to excavate a tunnel under Harvard Yard to do it. Harvard University objected. The MBTA took Harvard to court in order to exercise eminent domain and thus override Harvard's objection.
In court, the MBTA presented arguments for its position: the good that an extended Ⓣ Red Line would do for the people of Cambridge, Somerville, and the Boston metropolitan area generally.
Harvard's lawyer opened his briefcase, pulled out a letter sealed under glass, and presented it to the judge.
The judge read the letter, and summarily dismissed the MBTA's case.
The letter was an executive order perpetually exempting Harvard University from eminent domain, signed by George Washington, the first U.S. President.
Thus, in order to extend the Ⓣ Red Line, the MBTA had to go around Harvard Yard, which meant putting in a tighter radius turn into the subway extension plan than the subway train cars were designed to deal with. Ergo, the subway trains have to slow down near Harvard Square (no one wants a derailment), and they make a nasty squealing/grinding noise as they make that turn [the noise is nasty – I've ridden the Red Line many times and been subjected it].
Coda to the story: Harvard University is rather older than the United States of America. What else does Harvard have in its archives?