1. In 1827, the Baltimore & Ohio Railroad broke ground for the first commercial railroad in the United States. The line was initially intended to transport goods between Baltimore and the Ohio River, but would eventually expand to become one of the country's most important transportation networks.

2. On October 17, 1864, Confederate cavalry under General Jubal Early attempted to capture and loot the town of Frederick. Union troops, led by General Lew Wallace, successfully defended the town and prevented its destruction.

3. In 1904, the Great Baltimore Fire occurred, destroying more than 1,500 buildings in the city and causing an estimated $150 million in damage (equivalent to over $4 billion today). The fire burned for more than 30 hours and required assistance from firefighters from as far away as New York and Philadelphia.

4. On October 17, 1945, the historic C&O Canal ceased operations after nearly 100 years of service. The canal, which connected the Potomac River and the Ohio River, played an important role in the transportation of goods and people throughout the region during the 19th and early 20th centuries.

5. In 1979, the first National Apple Harvest Festival was held in Arendtsville, Maryland, celebrating the region's apple harvest and the state's rich agricultural history. The festival has since become an annual tradition, featuring a variety of apple-themed activities, crafts, and entertainment.