ST. PAUL, Minn. (WCCO) — Visiting our national parks and federal recreational areas is a summertime ritual for millions of tourists.

Like the lock and dam tour in downtown Minneapolis, visiting the majority of sites is free. Only 118 of 417 National Park Service sites have an entrance fee.

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But that luxury is also costly and in need of a fix. Federal budgets for park maintenance and visitor upgrades have been shrinking.

“The National Park Service has a $12 billion backlog of projects,” said Sharon Stiteler, a National Park Service Ranger. “So, if you’ve ever been to a park and wondered why a trail or bathroom is closed, it’s because we don’t have the money to maintain that.”

To help make up the shortage, entry fees have been rising. In December, Congress passed the Centennial Legislation to establish an endowment to pay for improvements and visitor services.

As a result, one of the sweetest of deals – the $10 senior lifetime pass – will see a substantial price hike.

Beginning Aug. 28, the price of the lifetime senior pass will increase to $80.

To lock in at the current price, seniors who are 62 and older are flocking to National Park Service visitors’ centers in St. Paul and Bloomington.

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“It’s been insane,” Stiteler said, referring the amount of traffic.

Visitor Pat Schaffer purchased hers Monday, explaining: “There’s this pass and I understand they’ll run out. But yes, they just got a new shipment.”

Schaffer doesn’t want to lose out in case the centers run out, which has happened as demand soars.

“We went to Yosemite and it was beautiful couple of months ago,” Schaffer said. “We really want to go to Glacier.”

Already, long lines and busy signals are greeting many seniors who are trying to cash in on the deal.

“It’s a great deal, if you just hit the western parks, it pays for itself in no time, whether at $10 or $80,” Stiteler said.

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Passes are also available at www.yourpassnow.com for $10, plus an additional $10 service fee.