Mount Rainier climbing fees will soon increase by $1 to $44 for adults and $31 for those 24 and younger, park officials announced last week.

The increase for the annual passes goes into effect Dec. 1, said park Superintendent Randy King in a statement.

The climbing fee was implemented in 1995, and an increase was approved after a series of public meetings last year. The 2011 increase allows the park to adjust the fee annually based on the U.S. Consumer Price Index.

The climbing fee is a special-use fee designed to offset cost of Mount Rainier National Park’s climbing program, including keeping the mountain clean, staffing the upper mountain and information centers, and providing gear and training for climbing rangers.

About 10,500 people attempt to climb the 14,411-foot mountain each year.