Comic-Con 2018 is getting under way this week in San Diego, where about a dozen licensed stores began selling recreational marijuana products on January 1st.

About 135,000 people are expected for this year’s Comic-Con fan festival and many of them might not be familiar with California’s marijuana laws, so we’re recapping them here:

Tanya Dibrova, left, dressed as Marvel Comics character Hela, and Liz Torres, dressed as Doctor Strange, arrive for Comic-Con International on Thursday, July 19, 2018, in San Diego. (AP Photo/Richard Vogel)

1. You must be at least 21 to buy marijuana in licensed stores. This rule is strictly enforced. Here is a map of where the legal stores are located.

2. You must use cash to buy marijuana. Credit cards are not accepted. Most stores feature ATMs.

3. If you buy marijuana, do not open it in your car or truck when you’re driving away. It is illegal to have open marijuana containers in vehicles.

4. You cannot smoke marijuana in public.

5. Few, if any, hotels, in or near the Gaslamp Quarter and Convention Center will allow you to smoke on their property.

6. You’re only allowed to smoke marijuana in private quarters.

Attendees gather at the San Diego Convention Center for Comic-Con International on Thursday, July 19, 2018, in San Diego. The annual pop culture convention runs through Sunday. (AP Photo/Richard Vogel)

7. Consumers should be very careful if they purchase food or drinks infused with marijuana. It can take a long time for the affect of the marijuana to kick it, which leads some people to think that the drug isn’t working. Don’t rush to eat or drink more. Give the drug at least 45 minutes to produce a high.

8. If you’re leaving San Diego by plane after Comic-Con, don’t place marijuana in your suitcase or in your clothes. It is illegal to carry pot on to a plane.

9. It also is illegal to transport marijuana from California to other states, including Nevada, where recreational marijuana is legal.

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