Roosevelt Arch

The Roosevelt Arch is a rusticated triumphal arch at the north entrance to Yellowstone National Park in Gardiner, Montana, United States. Constructed under the supervision of the US Army at Fort Yellowstone, its cornerstone was laid down by President Theodore Roosevelt (who just happened to be vacationing in the area. Before this it wasn't planned that he be there.)in 1903. The top of the arch is inscribed with a quote from the Organic Act of 1872, the legislation which created Yellowstone, which reads: "For the Benefit and Enjoyment of the People". The arch is constructed of hexagonal blocks of columnar basalt, quarried locally. The arch is 52 feet high. Two towers or buttresses flank the main archway, pierced by pedestrian passages with heavy wood doors. Yellowstone was the first national park in the world, and local citizens felt that it lacked the grand entrance that such an august place demanded

Mammoth Hot Springs Terraces

As one early visitor described the Mammoth Hot Springs, "No human architect ever designed such intricate fountains as these. The water trickles over the edges from one to another, blending them together with the effect of a frozen waterfall." The hot springs were an early commercialized attraction for those seeking relief from ailments in the mineral waters. Today, to preserve these unique and fragile features, soaking in the hot springs is prohibitted. Mammoth Hot Springs are a surface expression of the deep magmatic forces at work in Yellowstone. Although these springs lie outside the Yellowstone Caldera boundary, scientists surmise that the heat from the hot springs comes from the same magmatic system that fuels other Yellowstone hydrothermal areas. A large fault system runs between Norris Geyser Basin and Mammoth, which may allow thermal water to flow between the two. Also, multiple basalt eruptions have occurred in this area. Thus, basalt may be a heat source for the Mammoth area.