The Stair Climb is also a fundraiser event to support families of local fallen firefighters and the FDNY Counseling Services Unit.

This Saturday, September 11, more than a thousand people are expected to climb the steps of Red Rocks Amphitheatre in honor of the fallen firefighters of the FDNY who gave the ultimate sacrifice on September 11, 2001. The annual Colorado 9/11 Memorial Stair Climb sees each participant pay "tribute to a FDNY firefighter by climbing the equivalent of the 110 stories of the World Trade Center."

"Through firefighter and community participation we can ensure that each of the 343 firefighters is honored and that the world knows we will never forget," writes the event's website.

Please note that this year's Stair Climb is limited to just 1,200 participants. Register for the Stair Climb.

If you're unable to attend, you can still honor the FDNY firefighters by donating—help the event get to its goal of $75,000! So far, at the time of this writing, the fundraiser has achieved $70,918.87 in donations.

The National Fallen Firefighters Foundation is a 501(c)3 non-profit and hosts the event every year.

Will you be participating in this year's Colorado 9/11 Memorial Stair Climb? Sound off in the comments below.