FLAGSTAFF, Ariz. (AP) — The National Park Service is floating a steep increase to entrance fees at 17 of its most popular sites next year.

Visitors to the Grand Canyon and other parks would be charged $70 per vehicle, up from the current $30 fee. At others, the hike is $25 to $70.

A 30-day public comment period opened Tuesday.

The proposal comes less than two years after many of the parks that charge entrance fees became more costly. The rationale is the same this time around — to address a maintenance backlog and infrastructure projects.

The Park Service says it expects to raise $70 million a year with the latest proposal for parks mostly in the West.

The higher fees would apply during the five busiest, contiguous months. For most, that means May through September.

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