Open range areas are generally marked with signage and protected by a cattle guard.
From the en.wikipedia.org
The light-dark pattern of lines and pavement resembles a true cattle guard to animals.
From the en.wikipedia.org
The cattle guard is composed of a bi-layer rubber polymer that lays directly on ground.
From the en.wikipedia.org
Ten feet from the highway, and only 200 yards from the Pennsylvania Turnpike, the car was stopped by a cattle-guard gate.
From the time.com
An hour south of the Great Salt Lake, a two-lane blacktop crosses a cattle guard into a wild expanse of golden scrub grass.
From the time.com
Using a virtual cattle guard is cheaper than a true cattle guard, and can be used on higher-speed roads due to its smooth surface.
From the en.wikipedia.org
Soon after we formed the cattle battalion guard fighting off Yankee raiders.
From the news-journalonline.com
The cars must cross a remote stretch of Nevada desert, negotiating their way around standing water, boulders, deep ditches and the occasional cattle guard.
From the newscientist.com
They are also common throughout the Western United States and Canada, where they are usually called a cattle guard or, occasionally, a Texas gate.