"A serene, turquoise beach on Isla Mujeres, described as "famous for emerald waters and sandy sea shore." It sits within a region noted for Blue Flag recognition — Mexico boasts 77 Blue Flag-designated beaches and Isla Mujeres has four — and the designation signals more than cleanliness: Blue Flag is a "voluntary award for beaches, marinas, and sustainable tourism boats" that requires a "series of stringent environmental, educational, safety, and accessibility criteria," which must both be met and maintained. Blue Flag's website explained, "Environmental education activities must be offered and promoted in addition to a permanent display of information relevant to the site in terms of biodiversity, ecosystems, and environmental phenomena." Among the program's 33 criteria are requiring water quality to be displayed, keeping beaches clean, making trash containers available, ensuring "an adequate number of toilet or restroom facilities" for visitors, and — crucially — that "free access must be granted to the public." - Stacey Leasca Stacey Leasca Stacey Leasca is an award-winning journalist and co-founder of Be a Travel Writer, an online course for the next generation of travel journalists. Her photos, videos, and words have appeared in print or online for Travel + Leisure, Time, Los Angeles Times, Glamour, and many more. You'll usually find her in an airport. If you do see her there, please say hello. Travel + Leisure Editorial Guidelines