Because Texas was its own country, the border between Texas and Oklahoma is the TEXAS side of the Red River, not in the center of the Red River (as is traditional between states).
The US 75 is one of many roads that cross the TX-OK border here.
Both TX and OK have big tourist info centers at the first exits on their sides of the border.
The border between TX and OK has not always been quiet: (
visit link)
"RED RIVER BRIDGE CONTROVERSY.
The Red River Bridge controversy between Texas and Oklahoma (sometimes called the Red River War) occurred in July 1931 over the opening of a newly completed free bridge, built jointly by the two states, across the Red River between Denison, Texas, and Durant, Oklahoma. On July 3, 1931, the Red River Bridge Company, a private firm operating an old toll bridge that paralleled the free span, filed a petition in the United States district court in Houston asking for an injunction preventing the Texas Highway Commission from opening the bridge. The company claimed that the commission had agreed in July 1930 to purchase the toll bridge for $60,000 and to pay the company for its unexpired contract an additional $10,000 for each month of a specified fourteen-month period in which the free bridge might be opened, and that the commission had not fulfilled this obligation. A temporary injunction was issued on July 10, 1931, and Texas governor Ross S. Sterling ordered barricades erected across the Texas approaches to the new bridge. However, on July 16 Governor William (Alfalfa Bill) Murrayqv of Oklahoma opened the bridge by executive order, claiming that Oklahoma's "half" of the bridge ran lengthwise north and south across the Red River, that Oklahoma held title to both sides of the river from the Louisiana Purchase treaty of 1803, and that the state of Oklahoma was not named in the injunction. Oklahoma highway crews crossed the bridge and demolished the barricades. Governor Sterling responded by ordering a detachment of three Texas Rangersqv, accompanied by Adjutant General William Warren Sterling, to rebuild the barricades and protect Texas Highway Department employees charged with enforcing the injunction. The rangers arrived on the night of July 16. On July 17 Murray ordered Oklahoma highway crews to tear up the northern approaches to the still-operating toll bridge, and traffic over the river came to a halt. On July 20 and 21 mass meetings demanding the opening of the free bridge were held in Sherman and Denison, and resolutions to this effect were forwarded to Austin. On July 23 the Texas legislature, which was meeting in a special session, passed a bill granting the Red River Bridge Company permission to sue the state in order to recover the sum claimed in the injunction. The bridge company then joined the state in requesting the court to dissolve the injunction, which it did on July 25. On that day the free bridge was opened to traffic and the rangers were withdrawn.
Meanwhile, a federal district court in Muskogee, Oklahoma, acting on a petition from the toll-bridge company, had on July 24 enjoined Governor Murray from blocking the northern approaches to the toll bridge. Murray, acting several hours before the injunction was actually issued, declared martial law in a narrow strip of territory along the northern approaches to both bridges and then argued that this act placed him, as commander of the Oklahoma National Guard, above the federal court's jurisdiction. An Oklahoma guard unit was ordered to the bridge, and Murray, armed with an antique revolver, made a personal appearance in the "war zone," as the newspapers labeled it. No attempt was made to enforce the Oklahoma injunction, but on July 24, with the free bridge open, Murray directed the guardsmen to permit anyone who so desired to cross the toll bridge. On July 27 Murray announced that he had learned of an attempt to close the free bridge permanently, and he extended the martial-law zone to the Oklahoma boundary marker on the south bank of the Red River. Oklahoma guardsmen were stationed at both ends of the free bridge, and Texas papers spoke of an "invasion." Finally, on August 6, 1931, the Texas injunction was permanently dissolved, the Oklahoma guardsmen were withdrawn to enforce martial law in the Oklahoma oilfields, and the bridge controversy was laid to rest. The bridge was dynamited on December 6, 1995, to make room for a new one." [end]
However, today you can simply sail along US 75 at highway speeds.