Sun and Beach Tourism

If you are a person that enjoys relaxing under the sun, Mexico has gourgeous beaches for you to visit, they are located in the most beautiful places and you can really have a good time there.
Which beach would you consider or like to visit?
The truth is that in Mexico there are thousands of them and is difficult to pick one, but I think when choosing we take some things into account such as activities, places of interest and specially hotels.
You can practise many sports or do a lot of activities like going horse riding, snorkelling in the beautiful reefs, scuba-diving, fishing, surfing and many more. It is really tempting, I think it would be great to go.
Has anyone been to Mexico? Share you experience or any important fact about it.