This portion of an 1844 map, drawn by Josiah Gregg, shows the middle portion of the Red River. I like the detail on the labels. (David Rumsey Map Collection)
Notice there are two "Route[s] of Caravan from Chihuahua to Arkansas." The 1835 route started in Chihuahua City and extended to Fort Smith, and crossed the Red River at the old Coffee Trading Post near Cache Creek (before it was moved to Preston). The 1840 route crossed the Red River at Fulton, which was also its terminus. The caravans were trading expeditions between the Mexico and the U.S. The originators of the caravans had hoped to set up permanent trade routes, but due to economic panics, this never happened.
In the western portion of the map is the "Route of Texas Santa Fe Expedition 1841." This was an ill-fated attempt by the Lamar administration (Mirabeau Lamar, President of Texas from 1838-1842) to declare Santa Fe a part of Texas while also establishing a trade route that never materialized. The Texans got lost as they searched for the Red River, and ended up seeking help from Mexican traders who brought them to Santa Fe, where a military attachment awaited and imprisoned them.
Above Fort Washita is Chickasaw Depot, attached to a road that extends to Fort Smith. This is the place also known as Boggy Depot (which is actually located in the Choctaw Nation).
Another road leads from Fort Towson to Fort Smith because, during the mid-19th century, Fort Smith was truly the epicenter of the Southwest.
There are some ghost towns on this map, too: Warren, Doaksville, and Jonesboro. Little Eagletown in Indian Territory warrants a mention on this map, as do three Texas county seats: Bois d'Arc (aka Bonham), Clarksville, and DeKalb (briefly, the seat of Bowie County).
The Cross Timbers is well defined on this 1844 map by Josiah Gregg, both in depiction and explanation: "The Wacoes, Wichita's, Tawackanoes, Towyash, Keechyes, Caddoes, and Inyes reside chiefly on Red R. and its branches above the Cross Timbers." I know all of these tribes and affiliations save for the Inyes, which I'm going to need to investigate.