Join a free historic walking tour of the Flatiron district, led by professional guides this Sunday at 11 a.m. Learn more about the world famous Flatiron building, and other notable architectural icons, including New York Life Insurance Building and the MetLife Clock Tower from 1909. Ninety-minute walking tours take place year-round every Sunday, rain or shine, and meet at the tip of the Flatiron building at 23rd Street just east of Fifth Avenue. No advance registration is required. Tours are sponsored by the Flatiron/23rd Street Partnership Business Improvement District (BID).