In which U.S. city did Tesla build a laboratory in 1899 for high-voltage experiments?

Tesla built his high-voltage experimental laboratory in Colorado Springs in 1899. He constructed the facility to investigate high-frequency electricity, electrical discharges, and the possibility of transmitting power wirelessly.

The site, known as the Tesla Experimental Station, offered Tesla more space than his New York laboratory. Colorado Springs’ high altitude and relatively low-pressure air also made it useful for studying electrical breakdown and the behavior of enormous voltages. Construction began in May 1899 after Tesla arrived with assistants and a local contractor.

Inside the building, Tesla operated a huge magnifying transmitter, a specialized form of Tesla coil. Its dramatic electrical discharges produced some of the largest artificial sparks ever made at the time. Tesla recorded his observations in the Colorado Springs Notes, 1899–1900, which documented experiments relevant to wireless communication and power transmission.

Tesla used the laboratory for about a year and left Colorado Springs in 1900. The building was later dismantled in 1904 after legal and financial difficulties. The city therefore belongs to a distinct chapter of Tesla’s career, separate from his later Wardenclyffe project on Long Island.