The meeting point is at the stone bench in front of the entrance to the Mercado de la Merced on Avenida José María Morelos (between Insurgentes and Nicolás del Puerto). The bench and entrance are set back at the end of a parking lot, under a large sign that says "Mercado de la Merced.
The tour ends at Fonda Margarita in Mercado 20 de Noviembre