Do I really need a rental car?

Yes. While tour buses exist, they prevent you from visiting the less crowded cenotes early in the morning, which is the only way to enjoy them properly.

Can I drink the water?

No. Always drink bottled or filtered water, and use it even for brushing your teeth to avoid stomach issues.

How to plan a week in the Yucatán for cenotes and ruins

Base yourself in Valladolid for three nights to tackle the central ruins and cenotes, then move to Mérida for four nights to explore the Puuc route and coastal sites. Rent a car at the Mérida or Cancún airport to ensure you can reach the remote cenotes before the tour buses arrive at 10:00 AM.

Pick up your rental car. Do not rely on ADO buses if you want to see both ruins and cenotes in one day. Rent a car from a reputable agency at the airport. Ensure it has full insurance coverage, as road conditions can be unpredictable.
Prioritize your timing. Cenotes are best visited between 8:00 AM and 9:30 AM to beat the crowds. Ruins, especially Chichén Itzá, should be visited the moment they open at 8:00 AM to avoid the midday heat and heavy tour traffic.
Balance your itinerary. Mix your days: one day for major ruins, one day for 'cenote hopping' in a specific zone, and one day for colonial city exploration to avoid 'ruin fatigue.'

Do I really need a rental car?: Yes. While tour buses exist, they prevent you from visiting the less crowded cenotes early in the morning, which is the only way to enjoy them properly.
Can I drink the water?: No. Always drink bottled or filtered water, and use it even for brushing your teeth to avoid stomach issues.