Ellis Island
Ellis Island immigrants as depicted in a USPS stamp
Ellis Island, now a museum located in New York Harbor, was at one time the main immigration port for immigrants entering the United States in the late 19th and early 20th centuries. Some were sent back for reasons including chronic disease but most were allowed in. Many of these immigrants settled in New York for at least their first few years in America. The port opened on January 1, 1892 and was closed on November 29, 1954 but not before processing more than 20 million immigrants (12 million of which were allowed to pass through).
Ellis Island is also known as a place where people changed their names. If the immigration officer couldn't spell the original name, they'd come up with an approximation, or something shorter or simpler, such as "Ellen Pollock" for "Helena Polonowycz". This was especially common when the newcomer couldn't read and write English.
Ellis Island now houses a museum, reachable by ferry from the southern tip of Manhattan (New York City), and from Liberty State Park in Jersey City, New Jersey.