Most people assume a purple fence is just eccentric decor, but in many states it’s a legal line in the sand. Vertical purple stripes—about an inch wide, eight inches long, painted three to five feet off the ground and repeated every hundred feet—can carry the same legal weight as a “No Trespassing” sign. Hunters, hikers, and wanderers are expected to know: cross that line, and you’re no longer “just exploring.” You’re trespassing.