- Southern Terminus:
- Greenville Road (CR 519) at the New York-New Jersey state line
- Northern Terminus:
- Mountain Road (CR 35) and US 6 in Port Jervis
- 3.08 miles
Mountain Road is a north/south route in Orange County extending from the border with New Jersey to Otisville. Greenville Road (CR 519) becomes Mountain Road upon crossing the state line. The southernmost three miles are designation CR 55. At US 6, the designation changes to CR 35. The entire length is a two-lane undivided road.