<P> The Arbuckle Mountains are located in a small area nestled in between regions 29g and h; it is made of folded, rather than dissected, limestone, sandstone, and dolomite, and features the greatest topographical relief of the entire Cross Timbers, though not the highest elevations . The landscape includes many caves, sinkholes, springs, and streams . I - 35 crosses this region north to south . </P> <P> Part of the difference in the Cross Timbers region and the surrounding regions west (drier) and east (wetter) has to do with the Dry line which separates humid air from the Gulf of Mexico from the dry air of the Llano Estacado, the Texas Panhandle, and the High Plains . </P> <P> The thick growth formed an almost impenetrable barrier for early American explorers and travelers . Washington Irving, in 1835, described it as "like struggling through forests of cast iron ." Rachel Plummer, while a captive of the Comanche in 1836, described it as "a range of timber - land from the waters of Arkansas, bearing a southwest direction, crossing the False Ouachita, Red River, the heads of Sabine, Angelina, Natchitoches, Trinity, Brazos, Colorado...the range of timber is of an irregular width, say 5 to 35 miles wide...abounding with small prairies, skirted with timber of various kinds - oak, of every description, ash, elm, hickory, walnut and mulberry...the purest atmosphere I ever breathed was that of these regions ." Josiah Gregg described the Cross Timbers in 1845 as varying in width from five to thirty miles and attributed their denseness to the continual burning of the prairies . </P> <P> The Cross Timbers vary in width from five to thirty miles, and entirely cut off the communication betwixt the interior prairies and those of the great plains . They may be considered as the "fringe" of the great prairies, being a continuous brushy strip, composed of various kinds of undergrowth; such as black - jack, post-oaks, and in some places hickory, elm, etc., intermixed with a very diminutive dwarf oak, called by the hunters, "shin - oak ." Most of the timber appears to be kept small by the continual inroads of the "burning prairies;" for, being killed almost annually, it is constantly replaced by scions of undergrowth; so that it becomes more and more dense every reproduction . In some places, however, the oaks are of considerable size, and able to withstand the conflagrations . The Underwood is so matted in many places with grapevines, green - briars, etc., as to form almost impenetrable "roughs," which serve as hiding - places for wild beasts, as well as wild Indians; and would, in savage warfare, prove almost as formidable as the hammocks of Florida . </P>

Major attractions in the north central plains of texas