The line currently runs from the Essex campus of the Community College of Baltimore County to Turner's Station in Dundalk.

[7][8] The proposal to eliminate service to Ft. Howard drew protests that were filmed by local news stations.

A new Route 6 that ran from Eastpoint Mall to Ft. Howard, mostly via North Point Road, was briefly added in 1997, but was discontinued a year later.

In 2000, MTA extended Route 4 from Eastpoint Mall to White Marsh Mall through Essex and Rosedale, and south from the Dundalk loop to Turner's Station, and the route was slightly modified to serve the CCBC Dundalk campus.

This service initially operated through Essex along Mace Avenue, a street where buses were previously opposed by the community.

Selected trips also served the Yellow Brick Road industrial Park in Golden Ring.

On June 18, 2017 as part of the BaltimoreLink transit system overhaul, Route 4 was replaced in its entirety by LocalLink 62.