There are four Grand Slams:
Wimbledon is the only Grand Slam Tournament played on a grass court. Started in 1877, The Wimbledon Championships are held at the All England Club in London and is the oldest tennis tournament in the world. The tournament is currently played on 100% perennial ryegrass.
The US Open and Australian Open also were played on grass but changed surfaces in 1975 and 1988, respectively.
The French Open is played on a red clay surface.
The Australian Open
The French Open is the only one of the four Grand Slam tournaments to be played on clay courts.
Wimbledon is played on grass courts.
Grass and Clay
the Davis Cup and Wightman Cup tournaments
The most prestigious professional Grass Court Tennis Tournament is Wimbledon.
Asphalt gravel clay grass wood synthetic grass carpet