Maryland highway system
The Maryland highway system is a network of highways owned and maintained by the U.S. state of Maryland. In addition to the nationally numbered Interstate Highways and U.S. Highways, the highway system consists of a network of Maryland state-numbered highways. All three types of highways together provide access to all incorporated and unincorporated areas in all 23 counties of Maryland as well as the independent city of Baltimore. Highway systems. Interstate highways. Maryland has 16 Interstate highways, including six primary Interstates and ten auxiliary Interstates. The longest Interstate in Maryland is Interstate 95, while the shortest  Interstate is I-295. Maryland also contains an unsigned Interstate, I-595; a former Interstate, I-170; and an intracounty Interstate, I-97, which is also the shortest primary highway in the Interstate Highway System. U.S. highways. Maryland has 14 U.S. Highways, including seven primary U.S. Highways and seven auxiliary U.S. highways. The longest U.S. highway in Maryland is U.S. Route 40, while the shortest U.S. highway is US 522. Maryland also contains six former U.S. highways. Maryland state highways. Maryland has a unitary system of numbered state highways with numbers between 2 and 999. The longest Maryland state highway is Maryland Route 2 , while several state highways are less than in length. Most of the shortest highways are unsigned. Several state highways have multiple disjoint segments that are denoted internally by suffixes, encompassing either old alignments of a major highway or a collection of service roads related to a particular highway. Other systems. There are other systems of highways in Maryland that are not marked but are numbered internally. Highway agencies. Maryland State Highway Administration. The vast majority of Interstate, U.S., and state highways are constructed by and maintained by the Maryland State Highway Administration (MDSHA). Maryland Transportation Authority. All toll facilities in  the state and limited access highways within Baltimore except I-83 are constructed and maintained by the Maryland Transportation Authority (MdTA). Other agencies. All U.S. and state highways and I-83 within Baltimore are maintained by the Baltimore City Department of Transportation. Portions of U.S. and state highways within particular cities and towns are maintained by the respective municipalities.