It's worth a visit if you are in Merida for a few days. The building is a rather short walk from the main plaza in the midst of a shopping area used by the locals. It used to be the post office but has been renovated to become a very nice museum. You will learn about the history of this interesting city with explanations in both Spanish and English. Plus there is usually an art display to fill up areas not filled with the historical items. If you are pressed for time you could probably give this place a skip but do give it an hour if you are in town for a few days.