The Chicago Harbor Lighthouse we see today is actually the most recent in a line of lighthouses that helped transform the city into one of the world's busiest ports in the 1800s. The oldest was built in 1832 and stood near where the Michigan Avenue Bridge is today. But early harbor developments moved the river entrance further into the lake, triggering a need for a second lighthouse just two decades later.
The current structure has directed traffic into the river harbor for more than a century. When it was first constructed in 1893, it stood at the end of a jetty extending from the river mouth. It wasn't until 1917 that it was relocated to the outer breakwater.
Learn more about Chicago's rich maritime history at chicagowaterwalk.org.