Known as Stillpond Harmony Road, the highway runs 1.19 miles (1.92 km) from MD 292 in Still Pond east to MD 298 near Still Pond in northern Kent County.

MD 566 begins at an intersection with MD 292 (Still Pond Road) next to the George Harper Store in the Still Pond Historic District.

MD 566 heads east from the village as two-lane undivided Stillpond Harmony Road.

The highway reaches its eastern terminus at an acute intersection with MD 298 (Lambs Meadow Road).

[5] Those two segments were bypassed when MD 566 was placed on its present, straighter course through Still Pond in 1959.