Time Out says
These aren't the kind of posters you'd put on your dorm room wall. At Swann Galleries' annual auction, a single one might cost thousands of dollars. (For example, N.C. Wyeth's 1929 poster for the Pennsylvania Rail Road will likely sell for $1,500–$2,000.) But for four days, spendthrifts can visit Swann to feast their eyes on these colorful pieces for free.