Antonio Area Freeway System
Interstate 35 South (South PanAm Freeway)
|This page last updated November 22, 2021
||This page covers Interstate 35 west and south of
downtown San Antonio from the I-10 West interchange to Loop
1604. For information on I-35 north of downtown, see the I-35 North page.
Length: 16 miles
a result of
NAFTA and the development of the Eagle Ford Shale oilfield south of San
Antonio, I-35 South has become an increasingly important spoke in San
freeway system. This segment serves the city's southwest side
and continues on
to Laredo, the busiest US-Mexico border crossing for trucks. This
corridor is also an
important component in the continuing development of Port San
downtown San Antonio, Market Square, the University of Texas at San
downtown campus, the San Antonio Produce Market, South Park Mall, Palo
College, Texas A&M University at San Antonio, the
Toyota plant and adjacent suppliers, and a growing logistics
industrial area at Loop 410 as well as the cities of Von
Somerset. Commercial and industrial development fronts the
downtown. Residential and some commercial development lines
the corridor south
of US 90 to Somerset Rd. Mostly undeveloped land takes over south of
Rd. to Loop 410. South of Loop 410, light industrial areas and
two rail yards sit on the west side of
freeway between Loop 410 and Von Ormy.
- 8 lanes from I-10 West to Laredo
St. with a short double-decked stretch (4 lanes on
the upper levels; 4 lanes on the lower level) from Guadalupe St. to S.
- 9 lanes (4 southbound, 5
northbound) from Laredo St. to US 90
- 6 lanes from US 90 to Spur
- 4 lanes from Spur
422/Poteet-Jourdanton Hwy. to Loop 1604
- No traditional
access roads along most of the route
from I-10 West to US 90, although S. Pecos-La
Trinidad St. functions a
southbound access road from I-10 West to S Alamo St. Short sections of
access road exist on both sides between S Alamo St. and Cevallos St. A
road exists southbound from San Marcos St. to Nogalitos St.
- Continuous access roads along most of remainder of
- Access roads do not continue through Loop 410
interchange or over the Medina River, and the southbound access road
does not continue through the New Laredo Hwy. interchange
for a list of I-35 South exits.
mph from I-10 West to Loop 410
- 70 mph from Loop 410 to Loop 1604
|SPECIAL FEATURES &
- Two miles of I-10/US 87 concurrent
(multiplexed) from I-10 West to US 90
- US 81
was concurrent (multiplexed) over I-35 in Bexar County before it was
decommissioned south of Ft. Worth in 1991
- Double-decked freeway from just
north of S. Alamo to just south of S. Laredo St.
- TransGuide coverage from I-10
West to Southcross Blvd.
Metropolitan Transit Madla Transit Center just north of
- Northbound left exit to Loop 353
Generally heavy from I-10 West to SW
Military Dr. Moderate to light volumes south from
there. Regular peak-period congestion can be found northbound
in the morning between Division Ave. and Cesar Chavez Blvd. and in the
both directions between I-10 West and US 90.
ANNUAL DAILY TRAFFIC
|S of Laredo St.||179,000||159,000||173,964||179,100||171,936||149,584||-5.92%|
|S of US 90||159,000||135,000||152,614||157,581||158,210||137,738||+2.03%|
|N of SW Military Dr.||102,000||77,000||113,122||116,409||116,128||100,402||+30.39%|
|N of Zarzamora St.||63,000||68,000||80,924||87,092||90,788||78,772||+15.84%|
|N of Somerset Rd.||34,000||38,000||45,892||50,360||50,360||44,047||+15.91%|
|N of New Laredo Hwy.||33,000||35,000||43,677||45,927||48,590||39,984||+14.24%|
|S of Fischer Rd.||35,000||42,000||54,741||63,405||59,644||52,922||+26.00%|
for photos and video of this
current projects in
MPO's 25-year plan
has proposals for the expansion of I-35 to eight lanes from US 90 to
Atascosa County line.
new expressway (Kelly Parkway) roughly
paralleling this section of I-35 is proposed as part of the Port San
long-range road improvements package. It would run north from
SH 16 near the
Toyota plant to US 90 via General Hudnell Dr., crossing I-35 between
"stack" interchange at Loop 410 is included in future plans to upgrade
SW Loop 410.
first sections to be
built were simply called "US 81 Expressway", then
"South Expressway" and "Southwest Expressway" before being named
the "PanAm Freeway" as it
is a segment of the Pan American Highway. This
also part of the so-called "NAFTA
designation as I-35 was
authorized on October 1, 1959. US 81
south of Fort Worth in 1991.
section south of New Laredo Hwy. was built in 1934 as part
Arneson Plan to improve state highways in Bexar County. Prior to then,
US 81 and its predecessor SH 2 ran along Frio City Rd. and
was the first
expressway spoke in Bexar County to be completed from downtown to the
county line, although the section from Loop 410 to the county
was not upgraded to full Interstate standards until 1974.
- Late 1930s: The
section from Nogalitos St. to downtown was included as
part of the original three-legged expressway plan for San Antonio
designed to provide bypass routes
around downtown for through traffic on the various US highways. The
United States' entrance into World War II delayed these plans until
after the war.
- 1952: The
section from Guadalupe St. to Pruitt Ave. (just south of Nogalitos St.)
completed as one of the three spokes of the seminal expressway system.
- 1955: Alignment
routing of the section between Nogalitos St. and Loop 410. An earlier
proposal would have used the current routing from Nogalitos St. to SW
Military Dr., then would have followed SW
Military Dr. to New Laredo Hwy.
Access roads between SW Military Dr. and New Laredo Hwy. opened and the
pre-existing section of US 81 from New
Laredo Hwy. to the Atascosa county line was
upgraded to a "semi-freeway", which was a full divided highway with access roads but
no overpasses at intersections. The
elevated "Central Expressway" segment from
Guadalupe St. to present-day
I-10 West was completed including "Downtown Y" interchange.
- 1958: Access roads
between Nogalitos St. and SW Military Dr. opened.
- 1960: Freeway
between Nogalitos St. and Fischer Rd. completed including the Loop 410
- 1967: Interchange at
US 90 completed.
- 1974: Work to
upgrade the segment from Fischer Rd. to the Atascosa county line
to Interstate standards (mainly adding overpasses and exits) was completed.
- 1989: The
section from SW Military to Spur 422 expanded from four to six
- 1988-1991: Section
US 90 to I-10 West expanded as part of the "Downtown Y" project.
- 1995: TransGuide
coverage added from I-10 West to Southcross
Blvd. as part of the original TransGuide project.
- 2009: The
section from US 90 to Somerset Rd. was reconstructed. The
reconstruction removed several pedestrian bridges, expanded the
and frontage roads, relocated several entrance and exit
the previous southbound left-hand
exit to SP 422
and the northbound left-hand exit to Palo Alto Rd., and extended the
frontage road through the Spur 422 interchange.
ribbon cutting at SW Military Dr. looking north in 1960
courtesy of TxDOT)
I-35 over San Marcos St. looking
north ca. 1955
(Photo courtesy of TxDOT)
I-35 at Nogalitos St. looking
south ca. 1952
expressway ended here at this time. Southbound traffic exited onto
Nogalitos St., but northbound traffic entered the ramp shown here from
(Photo courtesy of TxDOT)