Since November 2011 you can participate in the walking tour Traces of Slavery in Utrecht. For more information look at the website Sporen van Slavernij Utrecht for more information. For a guided tour you can contact the organizers by mail.
In Amsterdam initiator and guide Jennifer Tosch offers the Black Heritage Amsterdam Tours on a weekly basis since 2013. For information and bookings see Blackheritagetours.com.
In other towns too, like The Hague using Pasado Presente (walking tour ‘Black Pioneers in the Hague’) or The Hague Historical Museum (city walking tour ‘The Hague and Slavery’), and Haarlem you can find similar tours. In Groningen both the Groninger Archieven and Mapping Slavery Groningen (under construction) offer tours.