If you are buying Premium gasoline here in California, it's often over $5 a gallon most places now

Why?

Because California uses gas taxes to rebuild and maintain our extensive highway and freeway system. It allows most of our freeways to be free except for a few toll roads and toll bridges that people can drive on if they if they want to pay for it. But, there are always alternate free routes too. 

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Fuel prices spike amid Ukraine crisis, with some markets hovering near $5 a gallon