Arizona State Route 77

Arizona State Route 77
State	AZ
Type	SR
Route	77
Maint	Arizona Department of Transportation
Length mi	237.72
Established	1930s
Direction a	South
Terminus a	I‑10 in Tucson
Direction b	North
Terminus b	US 89 near Show Low
Counties	Pima County, Pinal County, Gila County, Pinal County, Cochise County, Navajo County

Arizona State Route 77 is a state highway in the U.S. state of Arizona, running roughly south–north from Tucson to near Show Low. The route links metropolitan Pima County with growing communities in Pinal County, traverses the Gila River corridor, and provides access to regional centers including Casa Grande, Florence, Globe, and Payson. Historically part of early 20th‑century auto trails and later aligned with U.S. and state highway renumberings, the highway serves freight, commuter, and tourism traffic to destinations such as Saguaro National Park, San Pedro Riparian National Conservation Area, and the Tonto National Forest.

Route description

SR 77 begins at an interchange with I‑10 on the east side of Tucson and proceeds northeast as Oracle Road, passing near University of Arizona, Davis–Monthan Air Force Base, and the Rillito River. The corridor traverses the northern edge of Tucson Mountain Park and provides access to Catalina Foothills. North of Tucson the highway continues through Oracle and into Pinal County, intersecting I‑8‑access corridors and serving San Manuel and Mammoth. In the Casa Grande area SR 77 overlaps with I‑10 and SR 87 influences before reaching the historic Downtown Casa Grande and its proximity to Casa Grande Ruins National Monument.

Further north SR 77 follows the Gila River valley, connecting Florence—the seat of Pinal County—and providing links to Arizona State Prison Complex – Florence, Florence Historic Districts, and Florence Junction. The route climbs into the Tonto Basin and the Superstition Mountains approaches, intersecting with US 60 near Globe and providing a corridor to Miami and the Globe Historic Mining Districts. North of Globe SR 77 advances toward Payson, skirting the Tonto National Forest and offering access to recreational sites such as Mogollon Rim trails and Navajo‑area campgrounds, before terminating at a junction with US 60/US 89 near Show Low.

History

The corridor that became SR 77 was part of early auto trails and territorial roads used during the 20th century expansion of Arizona highways, linking frontier settlements such as Tucson, Florence, Globe, and Show Low. In the 1920s and 1930s realignments associated with the creation of the United States Numbered Highway System and later state route designations led to portions of the modern route being numbered under various state and U.S. routes including alignments with U.S. Route 80, U.S. Route 89, and early variants of SR 87. Post‑World War II growth, mining booms in the Globe-Miami district, and highway modernization programs by the Arizona Department of Transportation prompted paving, straightening, and bypass projects during the 1950s–1980s.

The late 20th century saw several jurisdictional changes as federal routes were truncated or reconfigured—interacting with projects involving I‑10 and US 60. Community‑level work in Casa Grande and Florence led to business route designations and urban realignments. More recently SR 77 has been affected by regional transportation planning efforts tied to population growth in the Sun Corridor and infrastructure funding initiatives from state and local partners including Pima Association of Governments and Central Arizona Governments.

Major intersections

Major intersections and junctions along SR 77 include the southern terminus at I‑10 in Tucson, connections with state and U.S. routes serving Casa Grande and Florence, a concurrency near Globe with US 60, and northern connections near Payson and Show Low with US 60 and US 89. Other notable junctions provide access to SR 79 in the San Tan Valley/ Florence Junction area and linkages to regional arterials connecting to Marana, Oracle, and San Manuel. The route intersects key freight and tourism corridors, facilitating movements between Port of Tucson logistics routes and recreation areas such as Saguaro National Park.

Future and planned improvements

Planned improvements to the corridor have been proposed by Arizona Department of Transportation and regional planning agencies to address congestion, safety, and freight needs amid growth in the Sun Corridor megaregion. Projects under study include capacity expansions near Tucson suburbs, intersection upgrades in Casa Grande and Florence, pavement rehabilitation across the rural segments near Pinal County ranchlands, and safety realignments in mountainous stretches approaching Payson. Funding considerations involve coordination with federal programs such as Federal Highway Administration grants and state bonding mechanisms administered under Arizona transportation plans. Local stakeholders including Pinal County, Pima County, municipal governments, and tribal nations near the corridor participate in public outreach and environmental analyses for proposed work affecting resources like Tonto National Forest and riparian areas.

Auxiliary routes and business loops

Over time auxiliary designations and business routes have served downtowns along the corridor, including business spurs serving Downtown Casa Grande and Downtown Florence. Historical alignments created by bypass projects led to local maintenance transfers to county and municipal authorities, with some segments designated as business loops connecting to historic districts and National Register properties in Globe and Florence. Coordination between the Arizona Department of Transportation, county jurisdictions, and local chambers of commerce influences the status and signage of remaining business routes and spur connections to tourist attractions such as Casa Grande Ruins National Monument and mining heritage sites in the Globe-Miami Historic Districts.

Category:State highways in Arizona Category:Transportation in Pima County, Arizona Category:Transportation in Pinal County, Arizona Category:Transportation in Gila County, Arizona Category:Transportation in Navajo County, Arizona