Where did immigrants go when they arrived to New York City?
Castle Garden was one of the first places immigrants reported to when they landed in New York City.  Before that, they just reported to the customs officer and then jwalked in.
Clipper Ship Approaching Castle Garden around 1866
A view of New York City Harbor from Castle Garden at Battery Park
The Barge Office located at the foot of Whitehall Street in lower Manhattan, 1890.  Before Elllis Island opened, this served as a temporary immigration station.
Continue on in time to New York's Ellis Island