Houston

===Roadways===

[[File:45intoI-10 2.jpg|thumb|The [[Interstate 10 in Texas|Interstate 10]]/[[U.S. Highway 90 (Texas)|U.S. Route 90]] and [[Interstate 45]] [[stack interchange]] northwest of Downtown Houston|alt=]]
The eight-county Greater Houston metropolitan area contains over {{Convert|25000|mi|km}} of roadway, of which 10%, or approximately {{Convert|2500|mi|km}}, is [[Limited-access road|limited-access highway]].<ref name=":1">{{Cite web |url=http://www.h-gac.com/taq/plan/2040/docs/2040-RTP-revised-April-2016.pdf |title=2040 Regional Transportation Plan |date=March 30, 2016 |website=Houston-Galveston Area Council (HGAC) |access-date=March 19, 2018 |archive-url=https://web.archive.org/web/20170908161824/http://www.h-gac.com/taq/plan/2040/docs/2040-RTP-revised-April-2016.pdf |archive-date=September 8, 2017 |url-status=live }}</ref> The Houston region's extensive freeway system handles over 40% of the regional [[Units of transportation measurement|daily vehicle miles traveled]] (VMT).<ref name=":1" /> [[Arterial road]]s handle an additional 40% of daily VMT, while [[toll road]]s, of which Greater Houston has {{Convert|180|mi|km}}, handle nearly 10%.<ref name=":1" />

Greater Houston possesses a [[Spoke–hub distribution paradigm|hub-and-spoke]] limited-access highway system, in which a number of freeways radiate outward from Downtown, with [[ring road]]s providing connections between these radial highways at intermediate distances from the city center. The city is crossed by three [[Interstate Highway System|Interstate highways]], [[Interstate 10 in Texas|Interstate 10]], [[Interstate 45]], and [[Interstate 69]] (commonly known as [[U.S. Route 59]]), as well as a number of other [[United States Numbered Highway System|United States routes]] and [[Texas state highway system|state highways]]. Major freeways in Greater Houston are often referred to by either the cardinal direction or geographic location they travel towards. Highways that follow the cardinal convention include [[U.S. Route 290]] (''Northwest Freeway''), Interstate 45 north of Downtown (''North Freeway''), Interstate 10 east of Downtown ''(East Freeway''), [[Texas State Highway 288]] (''South'' ''Freeway''), and Interstate 69 south of Downtown (''Southwest Freeway''). Highways that follow the location convention include Interstate 10 west of Downtown (''[[Katy, Texas|Katy]] Freeway''), Interstate 69 north of Downtown (''[[East Texas|Eastex]] Freeway''), Interstate 45 south of Downtown (''[[Gulf of Mexico|Gulf]] Freeway''), and [[Texas State Highway 225]] (''[[Pasadena, Texas|Pasadena]] Freeway''). {{Citation needed|date=October 2023}}

Three loop freeways provide north–south and east–west connectivity between Greater Houston's radial highways. The innermost loop is [[Interstate 610 (Texas)|Interstate 610]], commonly known as the ''Inner Loop'', which encircles Downtown, the [[Texas Medical Center]], [[Greenway Plaza]], the cities of [[West University Place, Texas|West University Place]] and [[Southside Place, Texas|Southside Place]], and many core neighborhoods. The {{Convert|88|mi|km|adj=on}} [[Texas State Highway Beltway 8|State Highway Beltway&nbsp;8]], often referred to as ''the Beltway'', forms the middle loop at a radius of roughly {{Convert|10|mi|km}}. A third, {{Convert|180|mi|km|adj=on}} loop with a radius of approximately {{Convert|25|mi|km}}, [[Texas State Highway 99|State Highway&nbsp;99]] (the ''Grand Parkway''), is currently under construction, with eight of eleven segments completed {{as of|2018|lc=y}}.<ref name=":3">{{Cite web |url=https://www.txdot.gov/inside-txdot/projects/studies/houston/sh99-grand-parkway.html |title=SH 99 / Grand Parkway Project |date=2022 |website=Texas Department of Transportation|archive-url=https://web.archive.org/web/20180304020957/https://www.txdot.gov/inside-txdot/projects/studies/houston/sh99-grand-parkway.html|archive-date=March 4, 2018|access-date=May 25, 2022}}</ref> Completed segments D through I-2 provide a continuous {{Convert|123|mi|km|adj=on}} limited-access tollway connection between [[Sugar Land, Texas|Sugar Land]], [[Richmond, Texas|Richmond]], [[Katy, Texas|Katy]], [[Cypress, Texas|Cypress]], [[Spring, Texas|Spring]], [[Porter, Texas|Porter]], [[New Caney, Texas|New Caney]], [[Cleveland, Texas|Cleveland]], [[Dayton, Texas|Dayton]], [[Mont Belvieu, Texas|Mont Belvieu]], and [[Baytown, Texas|Baytown]] .<ref name=":3" />

A system of toll roads, operated by the [[Harris County Toll Road Authority]] (HCTRA) and [[Fort Bend County Toll Road Authority]] (FBCTRA), provides additional options for regional commuters. The Sam Houston Tollway, which encompasses the mainlanes of Beltway 8 (as opposed to the [[frontage road]]s, which are untolled), is the longest tollway in the system, covering the entirety of the Beltway with the exception of a free section between Interstate 45 and Interstate 69 near George Bush Intercontinental Airport. The region is serviced by four spoke tollways: a set of [[managed lane]]s on the Katy Freeway; the [[Hardy Toll Road]], which parallels Interstate 45 north of Downtown up to [[Spring, Texas|Spring]]; the [[Westpark Tollway]], which services Houston's western suburbs out to [[Fulshear, Texas|Fulshear]]; and [[Fort Bend Parkway]], which connects to [[Sienna Plantation, Texas|Sienna Plantation]]. Westpark Tollway and Fort Bend Parkway are operated conjunctly with the Fort Bend County Toll Road Authority.

Greater Houston's freeway system is monitored by Houston TranStar, a partnership of four government agencies which is responsible for providing transportation and [[emergency management]] services to the region.<ref>[http://www.houstontranstar.org/about_transtar/ About Houston TranStar] {{Webarchive|url=https://web.archive.org/web/20120205224259/http://www.houstontranstar.org/about_transtar/ |date=February 5, 2012 }}. ''Houston TranStar.'' 2008. Retrieved on February 17, 2008.</ref>

Greater Houston's [[arterial road]] network is established at the municipal level, with the City of Houston exercising planning control over both its [[Municipal corporation|incorporated]] area and [[extraterritorial jurisdiction]] (ETJ). Therefore, Houston exercises transportation planning authority over a {{Convert|2000|mi2|km2|adj=on}} area over five counties, many times larger than its corporate area.<ref name=":2">{{Cite web |url=http://www.houstontx.gov/planning/transportation/docs_pdfs/2015_PolicyStatement.pdf |title=Major Thoroughfare and Freeway Plan Policy Statement |date=March 2015 |website=City of Houston |access-date=March 20, 2018 |archive-url=https://web.archive.org/web/20180321063323/http://www.houstontx.gov/planning/transportation/docs_pdfs/2015_PolicyStatement.pdf |archive-date=March 21, 2018 |url-status=live }}</ref> The ''Major Thoroughfare and Freeway Plan'', updated annually, establishes the city's [[street hierarchy]], identifies roadways in need of widening, and proposes new roadways in unserved areas. Arterial roads are organized into four categories, in decreasing order of intensity: ''major thoroughfares'', ''transit corridor streets'', ''collector streets'', and ''local streets''.<ref name=":2" /> Roadway classification affects anticipated traffic volumes, roadway design, and [[right of way]] breadth. Ultimately, the system is designed to ferry traffic from neighborhood streets to major thoroughfares, which connect into the limited-access highway system.<ref name=":2" /> Notable arterial roads in the region include [[Westheimer Road]], [[Memorial Drive (Houston)|Memorial Drive]], [[Texas State Highway 6]], [[Farm to Market Road 1960]], [[Bellaire Boulevard]], and [[Telephone Road]].