Baltimore County is located in central Maryland, borders Pennsylvania on the north and encircles Baltimore City on the south like a horseshoe. Most (about 80%) of the county is located in the piedmont plateau with gently rolling hills. The remaining 20% is in the coastal plain region with flat sandy soils. Within its beautiful valleys are located many thoroughbred horse farms . It is the third largest county in the State.
Baltimore County was formed by 1659. At that time it was made up more than one quarter of present-day Maryland and included parts of (or all of) today's Harford Co., Cecil Co., Frederick Co. & Carroll Co. The original county seat was at Spesutia Island, located in Joppa Town. In 1768, the county seat was moved to Baltimore Town. When Baltimore was incorporated as a city, the county seat was moved to its present location in Towson. Since 1851 Baltimore City and Baltimore County have been two completely separate entities.
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The county was named for the proprietor's Irish home, and today it is the home of the state's leading wine and horse industries.