Long a favored destination for park visitors, Morning Glory Pool was named in the 1880s for its remarkable likeness to its namesake flower. However, this beautiful pool has fallen victim to vandalism. People have thrown literally tons of coins, trash, rocks, and logs into the pool. Much of the debris subsequently became embedded in the sides and vent of the spring, affecting water circulation and accelerating the loss of thermal energy. Through the years Morning Glory's appearance has changed as its temperature dropped. Orange and yellow bacteria that formerly colored only the periphery of the spring now spread toward its center.
Image via Wikipedia