Unruly and eclectic, Los Angeles is home to an array of engineering and construction marvels that rivals any city in the world. No single word can sum up the L.A. experience, but the five marvels we profile give a sense of the breadth and scope of the city’s achievements: the new Red Line Subway system that barrels through a mountain range; the freeway system; Los Angeles Colisseum, built in 1923; the billion-dollar Getty Center that houses the family’s artwork; and Disneyland, the first theme park.