Baltimore City is an independent city (meaning it’s not part of any county). As such, it is the largest independent city in the U.S.
Snowballs/snowcones were invented in Baltimore during the Industrial Revolution.
The Great Baltimore Fire of 1904 burned for 30 hours, during which it destroyed 1,500 buildings and leveled entire neighborhoods. One of the reasons cited for the widespread destruction was mismatched hose couplings that impeded fire-fighting efforts. As a result of the Great Baltimore Fire, firefighting equipment was standardized across the United States.
The first dental school in the world was founded in Baltimore in 1840.
Baltimore has more statues and monuments per capita than any other city in the U.S.
The first telegraph line in the world was established between Washington, D.C., and Baltimore in 1844.
Source: See the rest of the article, “Fun Facts to Know and Tell About Baltimore”, in the free Baltimore Beacon, August 2018, Arts & Style, pages 22 and 25.