Maryland Route 273 (MD 273) is a state highway in the U.S. state of Maryland. Known for most of its length as Telegraph Road, the highway runs from U.S. Route 1 (US 1) near Harrisville east to the Delaware state line near Appleton, where the highway continues east as Delaware Route 273 (DE 273). MD 273 is the main east–west highway of northern Cecil County, connecting Conowingo (via US 1), Port Deposit (via MD 276), and Rising Sun with Newark, Delaware, via the communities of Calvert and Fair Hill, where the highway intersects MD 272 and MD 213, respectively. The state highway also provides access to the Fair Hill Training Center.