he building that houses the Theodore Roosevelt Rotunda is New York State's official memorial to the 26th president of the United States, who not only led expeditions for the American Museum of Natural History and augmented its collections with new species, but also strengthened the cause for national conservation. Designed by John Russell Pope, the Rotunda was dedicated in 1936 and declared a New York City landmark in 1967. It serves as the Museum's main entrance lobby, and is home to the Barosaurus exhibit, the world's tallest freestanding mount of a dinosaur.