Salmon pink is the predominant color of the sandstone from which the arch is carved. This color is modified by streaks of red extending down the sides of the structure. These stains are due to iron oxide, or hematite, which is soluble in water. As rain fell on the upper part of the arch, it dissolved some of the hematite and as the water moved down the sides it dried, leaving streaks of variegated colors—mostly reds and browns. The coloring becomes brilliant in the light of the late afternoon sun. This is probably the basis for the Indian legends that the arch is a rainbow changed to stone. [Illustration: _The trail descends 2,000 feet into Cliff Canyon_] _OTHER INTERESTING FEATURES_ Water dripping into the pools near the bottom of Rainbow Bridge Canyon is from rain water that has seeped down through the Navajo sandstone. When the water reaches impervious rock layers in the underlying Kayenta, it is concentrated, but eventually it seeps out along the walls of the canyon, forming springs. Plants grow in profusion nearby. Maidenhair fern and wild orchids are nestled in the shade. In addition, there are Indian paintbrush, loco, lupines, daisies, asters, yucca, sunflowers, evening-primroses, columbine, scarlet-bugler, and mariposa-lily. _ESTABLISHMENT AND REGULATIONS_ Rainbow Bridge was proclaimed a national monument on May 30, 1910, by President Taft. One hundred-sixty acres were placed under the protection of the National Park Service. The monument is a sanctuary for all wildlife, and hunting is prohibited. No plant life, other natural features, or Indian artifacts may be gathered, cut, destroyed, or removed from the monument. Visitors to the area are particularly advised that the defacing of native sandstone with names or dates is vandalism and that vandals will be prosecuted. _HOW TO REACH RAINBOW BRIDGE_ The bridge may be approached from three directions: 1. From U. S. No. 89 to Tuba City, Tonalea, and then Rainbow Lodge, where mules are available for the 14-mile trail trip. 2. From Mexican Hat by boat down the San Juan and Colorado Rivers to Forbidden Canyon and 6 miles on foot to the bridge. 3. From Lees Ferry 68 miles upstream by boat to Forbidden Canyon and 6 miles on foot to the bridge. Reservations for the boat trips should be made well in advance by addressing J. Frank Wright, Mexican Hat Expedition, Blanding, Utah, or Art Green, Soap Creek, Ariz., via Cameron, Ariz. _FACILITIES_ Meals, lodging, guide service, and mules are available at Rainbow Lodge from April 1 to November 15. Campers in the area should provide themselves with gasoline, oil stoves, or charcoal briquets. Firewood is not available, and the cutting of trees, dead or alive, is prohibited. A small spring under the bridge provides water for campers. _ADMINISTRATION_ Rainbow Bridge National Monument is a part of the National Park System administered by the National Park Service, United States Department of the Interior.