I am from Maryland, and have lived here the entirely of my nineteen years of existence.
Maryland is a great mix between North and South. It was a border state during the Civil War; we had slaves, but stayed in the Union, because Lincoln had the Maryland General Assembly placed under house arrest so they couldn't vote to secede, and put federal troops in out capital: Annapolis.
Maryland has a great cultural history and many historical places. There are the Civil War battlefields at Sharpsburg, where the famous Battle of Antiedam Creek was fought, the bloodiest day in American History (even more than 6 June, 1944), and the Prisoner of War camp at Point Lookout. The British landed here in the War of 1812, and fought several battles here, including the famous Seige of Fort McHenry, outside of Baltimore, where our national anthem was written.
Maryland has a great mix of terrain and climate, from the pine forests and Blue Ridge Mountains of the west to the rolling foothills of the Piedmont Plateau, to the costal plains of the Eastern Shore and Southern Maryland (where I live). The geography and economy of the state are centered around the Chesapeake Bay, which provides many good eats, including our famous Blue Crabs. If you come to Maryland, the one thing you abolutely MUST have is a true blue Maryland Crabcake; there simply is no parallel.
As I said, we are very culturally mixed; the areas around Baltimore and Washington D.C. are very Democratic and Nothern in culture, while the southern, eastern, and western parts are very rural and Southern. We are also the richest state in the nation IIRC; it comes mostly from the fact that everything important "in Washington" is actually in Maryland.
It's a beautiful state, when I get a chance, I'll take some pictures for you guys of at least the immediate area.