It’s one of the first questions you might ask before you travel to another country: is it safe to drink the tap water there? Not doing your homework could ruin your vacation and leave you with such maladies as diarrhea and hepatitis A.
The below infographic, compiled by Just the Flight, looks to help travellers know where it is and isn’t safe to drink. It uses data from the Centers for Disease Control and Prevention and goes country by country – blue means go ahead and drink, and red means stay away from tap water.
You’ll find entire continents deemed safe or unsafe to drink, which may overlook more localised water conditions. For instance, Armenia’s water is declared unsafe, yet I recently drank the tap water in the capital city of Yerevan for a month, and I never got sick or sprouted a tail.
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What to do if you’re in a red zone? Your best bet is to stick to drinking bottled or boiled water. Don’t take drinks with ice in them, and beware of eating foods such as fruit or salads, which may have been rinsed with tap water.
Just the Flight’s interactive graphic also includes the price of bottled water and beer around the world.
This article originally appeared on Yahoo Travel.