Question: Which highway runs through both Round Rock, Texas, and Saint Paul, Minnesota?

Context paragraphs:
University Avenue (Minneapolis–Saint Paul): University Avenue is a street that runs through both Minneapolis and Saint Paul, Minnesota.  It begins near the Minnesota State Capitol in Saint Paul and extends westward into neighboring Minneapolis, where it passes the University of Minnesota, and then turns north to pass through several suburbs before its main portion ends in Blaine, Minnesota, although there are stretches of road designated as University Avenue that are north of the Blaine terminus, the final stretch ending near Andree, Minnesota.  For many years, the road carried U.S. Highway 12 and U.S. Highway 52 (at least for part of its length), and University Avenue is still a significant thoroughfare in the area.

Larpenteur Avenue: Larpenteur Avenue (Ramsey County Road 30) is a main thoroughfare in Ramsey County, Minnesota, United States.  Originally named Minneapolis Avenue, it was renamed by the Saint Paul City Council in 1904 in honor of Auguste Louis Larpenteur, a fur trader and one of the original 12 citizens in the city of Saint Paul.  The west end of Larpenteur Avenue is at the border with Hennepin County in Lauderdale, immediately west of Minnesota State Highway 280.  Larpenteur continues east from Lauderdale through the cities of Falcon Heights, Roseville, and Saint Paul, where it is an exit off of Interstate 35E and bisected by Lake Phalen to the east.  It ends at Minnesota State Highway 120 (Century Avenue North) in Maplewood at the border of Washington County.

La Frontera (Round Rock, Texas): La Frontera is Round Rock's largest master-planned, multi-use commercial business-retail-housing center and is located at the northwest corner of SH 45 Toll Road and Interstate 35 in Round Rock, Texas within Williamson County, Texas.  La Frontera is also located immediately across Interstate 35 from the Dell international headquarters.  The name "La Frontera" means “the border” or “frontier” in Spanish, hence the name of the project which sits at the exact border of the two counties (Travis and Williamson) and two communities (Round Rock and Austin).  Because of the project's high profile, the entire area around this intersection over the years has loosely become known also as "La Frontera."

Round Rock Express: The Round Rock Express are a class Triple-A Pacific Coast League minor league baseball team in Round Rock, Texas, owned by RSR Sports (Nolan Ryan, Don Sanders, Reid Ryan) and founded by Reid Ryan, son of Baseball Hall of Famer Nolan Ryan.  The team is currently affiliated with the Texas Rangers.  Home games for the Round Rock Express are played at the Dell Diamond, a facility that is owned by the City of Round Rock and leased long-term to RSR Sports, who run and maintain the facility.  The team is named after the senior Ryan's pitcher nickname, "The Ryan Express".

Round Rock High School: Round Rock High School is a 6A high school within the Round Rock Independent School District in Round Rock, Texas.  During the late 1990s, it was the largest high school in Central Texas.

Education in Saint Paul, Minnesota: Saint Paul, Minnesota contains many educational institutions.  A number of educational "firsts" have happened in Saint Paul.  Hamline University, the first and oldest college in Minnesota, was founded in Saint Paul in 1854.  In 1991 Minnesota became the first state in the United States to pass legislation allowing the existence of charter schools.  The following year, the first charter school in the nation, City Academy High School, was established in Saint Paul.  The oldest library in Minnesota, the Minnesota State Law Library, was opened in 1849.

Interstate 35: Interstate 35 (IH-35 or I-35) is a major north–south Interstate Highway in the central United States.  I-35 stretches from Laredo, Texas, on the American–Mexican border to Duluth, Minnesota, at Minnesota Highway 61 (London Road) and 26th Avenue East.  Many Interstate Highways formerly had splits or spurs indicated with suffixed letters (N/S/E/W), and I-35 was the only one that still had such divisions, before the recent opening of I-69C, I-69E, and I-69W in South Texas.  In two stretches, both through twin cities, the highway splits into Interstate 35E—at Dallas and at Saint Paul, Minnesota—and Interstate 35W—at Fort Worth, Texas, and at Minneapolis.

West St. Paul, Minnesota: West Saint Paul is a city in Dakota County, Minnesota, immediately south of Saint Paul, Minnesota, and immediately west of South Saint Paul, Minnesota.  The city's misleading name comes in part from the fact that it lies on the west bank of the predominantly north-to-south Mississippi River.  A previous City of West St. Paul, incorporated in the late 19th century, was situated in what is now called St. Paul's Lower West Side.  According to the West 7th/Fort Road foundation, St. Paul annexed the West Side, and was incorporated for two reasons: "to aid law enforcement—criminals could escape St. Paul authorities by crossing to the West Side and Dakota County—and to eliminate the Wabasha Street Bridge tolls which were inhibiting development on the West Side."  The current West St. Paul split from the western half of South St. Paul, and was incorporated in 1889, just south of the city of St. Paul.  The population was 19,540 at the 2010 census, growing by 135 since 2000.  West Saint Paul is known for its 2.5-mile retail strip along Robert Street.

Minnesota State Fair: The Minnesota State Fair is the state fair of the U.S. state of Minnesota.  Its slogan is "The Great Minnesota Get-Together."  It is the largest state fair in the United States by average daily attendance.  It is also the second-largest state fair in the United States by total attendance, trailing only the State Fair of Texas, which generally runs twice as long as the Minnesota State Fair.  The state fairgrounds, adjoining the Saint Paul campus of the University of Minnesota, are in Falcon Heights, Minnesota, midway between the state's capital city of St. Paul and its largest city, Minneapolis, near the Como Park and Saint Anthony Park neighborhoods of Saint Paul.  Residents of the state and region come to the fair to be entertained, exhibit their best livestock, show off their abilities in a variety of fields including art and cooking, learn about new products and services, and enjoy many different types of food—often on a stick.  The fair runs for twelve days from late August into early September, ending on Labor Day.  The Minnesota State Fair was named the best state fair in the United States in 2015 by readers of USA Today.

Merriam Park Subdivision: The Canadian Pacific Railway Merriam Park Subdivision or Merriam Park Sub, also known as the Short Line, is a railway line in Saint Paul, Minnesota, which runs from Pig's Eye Yard and the CP River Subdivision in the east to the Short Line Bridge over the Mississippi River in the west, where rails continue as part of the Minnesota Commercial Railway.  It was named for John L. Merriam, a Minnesota banker and politician.  Completed by the Chicago, Milwaukee and St. Paul Railroad in 1880, it shortened the route Milwaukee Road trains took between downtown Saint Paul and downtown Minneapolis.  Previous trains would exit Saint Paul and follow the Mississippi River southwest until crossing at Fort Snelling where they would follow the path of today's Hiawatha Avenue (Minnesota State Highway 55) and METRO Blue Line toward the Milwaukee Road Depot.  Originally built as an interurban route, it was eventually converted for heavy rail traffic because the Twin City Rapid Transit streetcar system had taken over the local transit market.

Supporting paragraphs: La Frontera (Round Rock, Texas) Interstate 35
Answer: Interstate 35