At the sides of the bridge appear large sculptured disks, each 12 feet in diameter, and at the keystone of the arches there are buffalo heads 6 feet in height. These were also designed by Mr. Jennewein. The two sculptural groups at the entrance to the bridge will be symbolic of War. They were designed by Leo Friedlander, sculptor. At the entrance to the Rock Creek Parkway there will be two sculptural groups symbolic of Peace and the arts of Peace, designed by James E. Fraser, sculptor. There will be appropriate inscriptions carved on the bridge. [Illustration: COLUMBIA ISLAND PLAZA AND MEMORIAL AVENUE TO ARLINGTON NATIONAL CEMETERY] [Illustration: THE ARLINGTON MEMORIAL BRIDGE DEVELOPMENT, LOOKING TOWARDS THE LINCOLN MEMORIAL] At the center of the bridge is a drawspan, each leaf of which has a length of 92 feet, the height of an 8-story building. One minute is required for opening and closing the drawspan, which is operated by electricity. Each leaf weighs 6,000 tons. It is in itself an interesting achievement in bridge engineering. From Columbia Island westward there is the boundary channel bridge. From there to the Arlington National Cemetery is a memorial parkway 240 feet wide, 2,200 feet in length, lighted, lined with planting, and providing space at intervals for memorials. At Arlington National Cemetery there is a large memorial entrance, from which walks and driveways lead to the Tomb of the Unknown Soldier at the Memorial Amphitheater and to Arlington House. [Illustration: PLAN FOR DEVELOPMENT OF GREATER ARLINGTON] Not only was the Arlington Memorial Bridge built in a period of 7 years, but one of the finest compositions in city planning has been carried out in connection with it. In addition to the treatment on Columbia Island Plaza and the approach to Arlington National Cemetery, there is also the great plaza at the approach to the bridge at the Lincoln Memorial, a sea wall for the Riverside Drive leading to it, and the water gate--steps of granite 215 feet wide--nearby. The bridge was dedicated and opened for travel in 1932. CHAPTER XIX THE PARKS OF THE DISTRICT OF COLUMBIA The park system of the National Capital is under the jurisdiction of the National Park Service, Department of the Interior. Since 1871 in many ways, particularly municipal affairs, the National Capital has been in the lead among American cities. Having begun with a logical and well-thought-out plan for the original city, the new Federal City was provided with an ample system of public reservations and parks.