The suggested fee, more than double the current $30 being charged, would help raise revenue for improvements at the parks.
Proposed increases would affect 17 national parks during peak tourist seasons - mostly during summer months.
The National Park Service faces an estimated $11 billion maintenance backlog.
"The Service's proposed fee increases, which double or even triple existing entrance fees, threaten to put many Americans to the choice of beauty or bread and to distance them from the places in which so many experience the natural wonder of our great and unique nation", read a letter written to the Service's acting director.
The California parks included in this fee hike are Yosemite National Park, Sequoia and Kings Canyon National Parks, and Joshua Tree National Park.More news: Trump supporters confuse LeVar Burton for LaVar Ball on Twitter
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Becerra said the fee increase would greatly impact modest-income families. Individual entry fees would go up from $15 to $30.
- The National Park Service is giving people more time to weigh in on a proposed fee increase at 17 of its most popular parks, including Rocky Mountain National Park. If approved, the increases would go into effect in 2018.
Petitioners include California Attorney General Xavier Becerra and 10 other attorneys general of Arizona, District of Columbia, Maine, Maryland, Massachusetts, New Mexico, New York, Oregon, Rhode Island, and Washington. It is not known whether the same thing would happen if fees are raised again.
According to an NPS press release, the comment period has been extended to December 22, 2017. While acknowledging the park service's maintenance backlog, the attorneys general said President Donald Trump should turn to Congress for additional funding.