A compact, well-designed centre dedicated to Zamenhof's life and language, occupying a fine pre-war building near the centre. The exhibition covers his Białystok childhood, his ophthalmology practice in Warsaw, the publication of the Unua Libro, and the curious survival and global spread of Esperanto through to the present day. There are listening stations where you can hear the language spoken and a children's classroom that runs introductory sessions.
The centre also functions as a cultural hub, with talks, films, and exhibitions on multilingualism and central European history. Allow an hour. The Zamenhof family house no longer stands, but a marker on Zamenhofa street shows where it once was.