Immigration to Ellis Island peaked between 1892 and 1924, during which time the 3.3-acre island was enlarged with landfill (by the 1930s it reached its current 27.5-acre size) and additional buildings were constructed to handle the massive influx of immigrants. During the busiest year of operation, 1907, over 1 million people were processed at Ellis Island.
With America’s entrance into World War I, immigration declined and Ellis Island was used as a detention center for suspected enemies. Following the war, Congress passed quota laws and the Immigration Act of 1924, which sharply reduced the number of newcomers allowed into the country and also enabled immigrants to be processed at U.S. consulates abroad. After 1924, Ellis Island switched from a processing center to serving other purposes, such as a detention and deportation center, a hospital for wounded soldiers during World War II and a Coast Guard training center. In November 1954, the last detainee, a Norwegian merchant seaman, was released and Ellis Island officially closed.
Beginning in 1984, Ellis Island underwent a $160 million renovation, the largest historic restoration project in U.S. history. In September 1990, the Ellis Island Immigration Museum opened to the public and today is visited by almost 2 million people each year.