Sol LeWitt came to fame in the late 1960s for his wall drawings and modular "structures" made of materials like aluminum and steel. His use of open, cubic forms originated from the cube shape, which influenced his artistic thinking from early on. Over time, he transitioned from closed wooden box-like sculptures to revealing the skeletal structures underneath by removing surfaces altogether. One of LeWitt's influential modular structures is in the collection of the Toledo Museum of Art.