Alexanders Run is a long 1st order tributary to Harmon Creek in Brooke County, West Virginia. This is the only stream of this name in the United States.
Alexanders Run rises at Weirton Heights, West Virginia, and then flows south-southwest to join Harmon Creek about 1 mile northwest of Colliers.
Alexanders Run drains of area, receives about 40.0 in/year of precipitation, has a wetness index of 339.87, and is about 59% forested.