Complex sentence: In 1957, he was awarded a major one man exhibition at the Grand Central Art Galleries, Biltmore Hotel, located in Grand Central Station, New York, where he was the youngest artist to ever exhibit in that venue up until that time.
Split into simpler sentences: In 1957, he was awarded a major one man exhibition at the Grand Central Art Galleries, Biltmore Hotel, located in Grand Central Station, New York. He was the youngest artist to ever exhibit in that venue up until that time.