One of the earliest flour mills in what is now Baltimore was located on Jone's Falls. John Hanson, a mill-wright, purchased the mill seat and 31 acres in 1711 from Charles Carroll. The site was part of a larger tract called Cole's Harbor. The mill remained until at least 1825, and it was described as sitting near the northwest corner of Bath and Holliday Streets.
Holliday Street is probably familiar to many who travel around in Baltimore, especially those who frequent the Baltimore Farmer's Market. But Bath Street? Here's a view from the early 20th century:
Today, Bath street exists under the Orleans Street overpass bridge. It's that little street where city vehicles are parked on both sides. And the mill site? Probably now a city impound lot. Though, it's very difficult to tell with all the changes due to the Jones Falls Expressway.
It's quite a different place now, 300 years later.