The first indoor arena was Madison Square Garden in New York City. It was completed in 1890 to replace the converted train station, which had been used for public events since 1874. The 1890 arena was replaced in 1925. Today’s Madison Square Garden opened in 1968 on the site of the former Pennsylvania Station. Chicago Stadium, opened in 1928 with a seating capacity of 21,000, was for many years the largest indoor arena in the world. Such arenas were used for circuses, ice shows, concerts, conventions and some sporting events – basketball and hockey games, tennis and boxing matches. Arena soccer was designed for the use of such venues, but they were not suitable for regular soccer or baseball games. Buildings built for these sports did not appear until the 1960s. The first was the Palazzo dello Sport, built in Rome for the 1960 Olympics. Designed by the famous architect Pier Luigi Nervi, it had a ribbed dome.
The much larger Houston Astrodome was completed in 1965. It seated 66,000 people, more than three times the capacity of a large indoor arena. In the sense that it was built for baseball and soccer – games that used to be played outdoors – it was the world’s first weatherproof stadium. Spectators in the Astrodome are fully protected from the weather by a dome of plastic windows that spans 642 feet (196 meters) and rises 208 feet (63 meters) above the playing field. The cabin is climate-controlled at 74° F (23° C). The largest stadium in the United States since the 1960s was built like the Astrodome.
Built in 1975, the Superdome in New Orleans is a 30-story building with a capacity of 97,000 people. The Detroit Lions, Silverdome, was built in Pontiac, Michigan, the same year. The Hubert H. Humphrey Metrodome (1982) in Minneapolis, Minnesota, is used for both baseball and soccer.
Stadiums with sliding roofs are ideal for all-weather play. The first Grand Slam tennis final ever held indoors was the 1988 Australian Open, which debuted at the convertible National Tennis Center in Melbourne. The four-section 66,000-seat SkyDome roof, built in Toronto in 1989, can be opened or closed in 20 minutes.