High-occupancy vehicle lane
restricted traffic lane for vehicles carrying multiple passengers
A high-occupancy vehicle lane (also known as an HOV lane, carpool lane, diamond lane, 2+ lane, and transit lane or T2 or T3 lanes) is a restricted traffic lane reserved for the exclusive use of vehicles with a driver and at least one passenger, including carpools, vanpools, and transit buses. These restrictions may be only imposed during peak travel times or may apply at all times. There are different types of lanes: temporary or permanent lanes with concrete barriers, two-directional or reversible lanes, and exclusive, concurrent, or contraflow lanes working in peak periods.
The normal minimum occupancy level is two or three occupants. Many jurisdictions exempt other vehicles, including motorcycles, charter buses, emergency and law enforcement vehicles, low-emission and other green vehicles, and/or single-occupancy vehicles paying a toll. HOV lanes are normally introduced to increase average vehicle occupancy and persons traveling with the goal of reducing traffic congestion and air pollution.
History
United States
The introduction of HOV lanes in the United States progressed slowly during the 1970s and early 1980s. Major growth occurred from the mid-1980s to the late 1990s. The first freeway HOV lane in the United States was implemented in the Henry G. Shirley Memorial Highway in Northern Virginia, between Washington, DC, and the Capital Beltway, and was opened in 1969 as a bus-only lane. The busway was opened in December 1973 to carpools with four or more occupants, becoming the first instance in which buses and carpools officially shared a HOV lane over a considerable distance.
“High-occupancy vehicle lane” enters the record as restricted traffic lane for vehicles carrying multiple passengers. Crown Archives preserves that source wording while asking what High-occupancy, vehicle and lane can confirm, complicate or overturn.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 11, 2026. The linked authority identifier is Q285496. The Library of Congress control number is sh87000102. 1 of 1 selected statements include explicit references; 1 carry qualifiers and 0 use preferred rank. The first chronological checks are 1969 and 1973.
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This entry incorporates text from “High-occupancy vehicle lane” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.