<P> Of the current four Grand Slam tournaments , the Australian and US Open use hard courts , French Open is played on clay , and Wimbledon , the only Grand Slam to have always been played on the same surface , is played on grass . The Australian Open switched to hard courts in 1988 and in its early years the French championship alternated between clay and sand / rubble courts . The US Open is the only major to have been played on three surfaces ; it was played on grass from its inception until 1974 , clay from 1975 until 1977 and hard courts since it moved from the West Side Tennis Club to the National Tennis Center in 1978 . </P>
<P> Of the current four Grand Slam tournaments , the Australian and US Open use hard courts , French Open is played on clay , and Wimbledon , the only Grand Slam to have always been played on the same surface , is played on grass . The Australian Open switched to hard courts in 1988 and in its early years the French championship alternated between clay and sand / rubble courts . The US Open is the only major to have been played on three surfaces ; it was played on grass from its inception until 1974 , clay from 1975 until 1977 and hard courts since it moved from the West Side Tennis Club to the National Tennis Center in 1978 . </P>
what are the tennis courts at wimbledon made from
what are the tennis courts at wimbledon made from
grass
grass