How did the vanderbilts make their money?

The Vanderbilts made their fortune primarily through the shipping and railroad industries. Cornelius Vanderbilt began by building a successful ferry service and then expanded into railroads, consolidating various lines to create a vast transportation network. His strategic investments and aggressive business tactics allowed him to dominate the industry, leading to immense wealth. The family's wealth continued to grow through the investments of subsequent generations in various enterprises, including real estate and philanthropy.