I love historical menus. The New York Public Library has a fantastic selection up, asking for people to check the transcriptions. This might mean there are some check marks over menu items, but you can click those off and get a sense of what restaurants used to serve. As an example, here are a couple of pages the menu from Cronin’s, March 3, 1961.
I don’t know about you, but I could use the occasional 55 cent Manhattan.