Delmarva

The Delmarva Peninsula is a large peninsula on the east coast of the United States. It's name comes from Delaware, Maryland, and Virginia (Abbreviated VA) combined into one word. The Delmarva Peninsula is a flat and sandy region mostly associated with coastal cities and seafood, and is the location for the fictional town of Beach City in Steven Universe.

Ronaldo Fryman stated on his blog Keep Beach City Weird that Old Bay is popular in Beach City, implying Beach City is in the state of Maryland. This is further strengthened by the fact Ronaldo mentioned DelmarvaCon is held every year in 'Charm City', the nickname for Baltimore which is also found in Maryland and 'isn't too far of a drive' from Beach City.