Apparently an exciting place to visit between 2 and 4 in the morning
Opened in 1926, this "grand old pile" was built by the Bronx Society for the Prevention of Cruelty to Children, which I believe was the Bronx branch of the world's first child protective agency. You can still see a remnant of that era on the entablature above the upper set of columns; it looks like it once read "Children's Shelter". The building currently serves as the BronxWorks Community Center, and features an indoor pool that was recently brought back to life.
The interior of the Bronx General Post Office is most notable for its thirteen large frescoes illustrating "the nobility of the American worker", but it's also home to some charming Postal Service-themed artwork, including You Can Mail Around The World and Postmasters Through The Years.