Rainbow Bridge.National Monument Utah. - Rainbow Bridge National Monument Is Administered By Glen Canyon National Recreation Area, Southern Utah, United States. Rainbow Bridge Is Often Described As The World's Highest Natural Bridge. The Span Of Rainbow Bridge Was Reported In 1974 By The Bureau Of Reclamation To Be 275 Feet (84 M), But A Laser Measurement In 2007 Has Resulted In A Span Of 234 Feet (71 M).[citation Needed] At The Top It Is 42 Feet (13 M) Thick And 33 Feet (10 M) Wide. The Bridge, Which Is Of Cultural Importance To A Number Of Area Native American Tribes, Has Been Designated A Traditional Cultural Property By The National Park Service. Photo