 U.S. Route 15 | ||||
|---|---|---|---|---|
 US 15 highlighted in red | ||||
| Route information | ||||
| Maintained by MDSHA | ||||
| Length | 37.85 mi[1] (60.91 km) | |||
| Existed | 1927[2]–present | |||
| Tourist routes |  Journey Through Hallowed Ground Byway Chesapeake and Ohio Canal Scenic Byway Old Main Streets Scenic Byway | |||
| Major junctions | ||||
| South end |  US 15 at Virginia border in Point of Rocks | |||
| North end | US 15 at Pennsylvania border near Emmitsburg | |||
| Location | ||||
| Country | United States | |||
| State | Maryland | |||
| Counties | Frederick | |||
| Highway system | ||||
| ||||
U.S. Route 15 (US 15) is a part of the United States Numbered Highway System that runs from Walterboro, South Carolina, north to Painted Post, New York. In Maryland, the highway runs 37.85 miles (60.91 km) from the Virginia state line at the Potomac River in Point of Rocks north to the Pennsylvania state line near Emmitsburg. Known for most of its length as Catoctin Mountain Highway, US 15 is the primary north–south highway of Frederick County. The highway connects the county seat of Frederick with Point of Rocks, Leesburg, Virginia, and Charles Town, West Virginia (via US 340), to the south and with Thurmont, Emmitsburg, and Gettysburg, Pennsylvania, to the north. US 15 is an expressway throughout the state except for the portion south of MD 28. The highway is a freeway along its concurrency with US 340 and through Frederick, where the highway meets US 40 and Interstate 70 (I-70). US 15 has a business route through Emmitsburg.
US 15 is the descendant of a pair of turnpikes that connected Frederick with Emmitsburg to the north and Buckeystown to the south. These turnpikes were reconstructed as state roads in the 1910s north of Frederick and in the early 1920s from Frederick south to Tuscarora. When US 15 was assigned in 1927, the Tuscarora–Point of Rocks highway had yet to be improved; this section was paved in the early 1930s. The modern Point of Rocks Bridge was built in the late 1930s after its predecessor was destroyed in a flood. The Frederick Freeway was constructed in the 1950s. US 15 was relocated to part of the freeway; the old route of the U.S. Highway through downtown Frederick became part of Maryland Route 355 (MD 355). US 15's present highway between Point of Rocks and Jefferson was constructed in the late 1960s; the old road south of Frederick was replaced with MD 28 and MD 85. North of Frederick, the U.S. Highway bypassed Thurmont and Emmitsburg in the late 1950s and mid-1960s, respectively. US 15 was upgraded to a divided highway north of Frederick in the early 1980s.