lots of indoor play
Lots of indoor rides, there are indoor walk through exhibits, also they have lots of spaces throughout the park that are covered where kids can play with legos and do things like design lego cars and race them. We got caught in a 90 minute terential downpour while at the park so we stopped had lunch then checked out the indoor exhibits and then my kids built lego structures and loved it!
Explore the Legoland hotel, the ninjago ride is indoors, build Legos in one of the little shops,... Wait it out and go have fun!
Not too many indoor activities.
There is an aquarium that could keep you occupied for about an hour.
Surf
If you have the hopper pass, you can always do the Sea Life Aquarium right next door. Admission is separate from Legoland.
It's San Diego. It never rains all day. Trust me, I live 10 min. away.
Go to the Costco next door or the Museum of music
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