Shell Building - Credit: Wikimedia Commons
The Shell Building is an office building in downtown St. Louis, Missouri. Located at the corner of Locust Street and 13th Street, known as Shell Corner, the 13-story, , building was the original home of the Shell Oil Company in the United States. The building has a rounded footprint, following the curve of Locust onto North 13th Street. Read more on Wikipedia
Source: en.wikipedia.org