Antoni Gaudi was a Spanish architect known for his highly original, curvilinear designs. He developed a unique modernist style that blended Gothic and Art Nouveau influences. His most famous work is the still-incomplete Sagrada Familia basilica in Barcelona, which features undulating stone facades and towers topped with colorful mosaics. Gaudi also designed Casa Mila and Casa Batlló, two Barcelona apartment buildings that utilized his innovative structural system of leaning columns and lightweight tile vaults. Through organic, nature-inspired forms, Gaudi sought to express the beauty of craftsmanship and go beyond conventional architectural styles.