1969

Alvord Lake Bridge, along with many of Ernest Ransome's reinforced concrete buildings, survived the 1906 San Francisco earthquake and several subsequent tremblers with no damage. Built in 1889 by Ernest L Ransome of New York, this reinforced concrete arch bridge in San Francisco's Golden Gate Park is believed to be the oldest concrete bridge in the United States that used steel reinforcing bars to improve the behavior of the concrete. The reinforcement consists of a series of square cold-twisted steel reinforcing bars, an invention of Ransome.

Built with a single set of tracks consisting of hardwood rails and wooden ties, and using wooden trestles to carry it over low-lying areas, the 136-mile Charleston-Hamburg Railroad was one of the longest railroads in the world when it was completed in 1833. It also became the first railroad in the United States to be powered entirely by steam, the first to carry mail under contract, and the first to provide regularly scheduled passenger service.