Houston is a sprawling, warm, and diverse city built on energy, medicine, and spaceflight. Space Center Houston tells the story of human spaceflight with spacecraft and mission history, the Museum District gathers museums for fine art, natural science, and contemporary work within a few miles, and Hermann Park offers green lawns, a lake, and a Japanese garden near the Texas Medical Center. Buffalo Bayou Park gives downtown a green corridor for walking and cycling, and the Theater District hosts opera, ballet, symphony, and stage productions.