The Art Institute building has the unusual property of straddling open-air railroad tracks. Two stories of gallery space connect the east and west buildings while the Metra Electric and South Shore lines operate below. The lower level of gallery space was formerly the windowless Gunsaulus hall, but is now home to the Alsdorf Galleries showcasing Indian, Southeast Asian and Himalayan Art. During renovation, windows facing north toward Millennium Park were added. The gallery space was designed by Renzo Piano in conjunction with his design of the Modern Wing and features the same window screening used there to protect the art from direct sunlight. The upper level formerly held the modern European galleries, but was renovated in 2008 and now features the Impressionist and Post-Impressionist galleries.