What Ports were used for Immigrants in the 1850s?

In the 1850s, Ellis Island in New York Harbor became one of the most significant ports for immigrants arriving in the United States, although it officially opened in 1892. Prior to that, many immigrants entered through Castle Garden, also in New York, which served as a reception center from 1855. Other important ports included Boston, Philadelphia, and Baltimore, where immigrants arrived primarily from Europe seeking better opportunities. These ports played crucial roles in shaping the demographic landscape of the U.S. during this period.