Casa de Montejo is the pink building on the Plaza Grande. The building was formerly the house of the Montejo family, who conquered the Yucatan Peninsula for Spain in the 1500's. The family lived in the house until the late 20th-century, when the Banamex moved in and set up a branch. Fortunately, Banamex allows visitors to visit a handful of rooms of the house for free during normal business hours. Each room is ornately decorated with items from all over the world. It definitely doesn't take long to see all the rooms, but it is well worth a half-hour stop.
As an aside, there is a store called Taller Maya in the Case de Montejo complex. The store has handicrafts made by Mayan artisans and claims to support fair trade with them for their work. It's worth a visit inside just to ogle the beautiful (but unfortunately pricey) items
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