An agency in the centre of Valladolid running day trips across eastern Yucatán: Ek Balam, the Maya city half an hour north whose main pyramid you may still climb and whose stucco frieze is among the best-preserved anywhere; Río Lagartos for the flamingos; Chichén Itzá, Izamal, Cobá and the Punta Laguna monkey reserve.
Valladolid's advantage over Cancún or Mérida as a base is distance: Chichén Itzá is forty minutes away, so you can be at the gate when it opens rather than arriving with the coaches at eleven.
A second line, +52 985 108 2018, reaches the same office. No WhatsApp number is published.