Riding the Tren "El Insurgente" between Santa Fe and Zinacantepec. This is the new CDMX to Toluca Commuter train, which, when complete, will link to the metro station at Observatorio.
More museums, art galleries and expos that you can visit for free; most of which are totally free, that's free for everyone, every day but I have included a few that are only free on selected days, even for non-locals, in Mexico City in 2022.