In the late 1800s, visitors to Walnut Canyon commonly dug through its dwellings for souvenirs, an acceptable and even promoted practice at the time. One woman, writing of a trip reported in the San Francisco Call about 1890, recalled digging for more than an hour and carrying away items including cornstalks, corncobs, beans, gourds, nuts, reeds, arrows, bowstrings, coarse cloth, a child's sandal, a measuring stick with regular notches, worn hardwood sticks, bone needles, a fish line, soapweed needles, and broken pottery. Such activity destroyed a number of rooms in Walnut Canyon. At the same time, other visitors and local citizens, moved by the canyon and outraged by the looting, pressed for federal protection, and on November 30, 1915, President Woodrow Wilson established Walnut Canyon National Monument. Today these sites are recognized as part of living cultures, removing or digging for relics is illegal, and even sitting or leaning on walls can cause irreparable damage.