The highway runs 17.61 miles (28.34 km) from Chesapeake Avenue in Crisfield east to U.S. Route 13 (US 13) in West Pocomoke.

The portion of MD 667 between Hudson Corner and West Pocomoke serves the community of Rehobeth.

This segment, which was built as Maryland Route 406, serves as a shortcut allowing traffic between Crisfield and Pocomoke City to avoid Westover at the junction of MD 413 and US 13.

MD 406 started as a short segment of modern highway east from Hudson Corner in the late 1920s.

The highway curves north, then veers northeast parallel to MD 413 through the village of Hopewell.

The highway leaves the suburban area surrounding Crisfield and enters a rural area as it continues northeast past St. Peter's Church Road, which leads toward St. Peter's Methodist Episcopal Church and Crisfield Municipal Airport.

The highway veers northeast at Burnettsville Road and north as it reaches the hamlet of Hudson Corner.

[5] The gap between Hopewell and Marion and improvement of Chesapeake Avenue within Crisfield were not completed by 1915; both segments were built as concrete roads by 1921.

[8][18] The original segment of MD 406 and the remainder of Rehobeth Road were relocated to the modern alignment, paved, and widened to 20 feet (6.1 m) in 1953 and 1954.