Denali National Park in winterTim Rains / National Park Service

It is the final Friday in the month of August, which means it is the final Friday of summer. Implausibly, something nice is happening on social media.

This week is the 100th anniversary of the National Park Service: A century ago on Thursday, Congress transferred America’s budding national park system from the control of the U.S. Army to a single civilian service. It charged the new organization both with conserving the wilderness and making it available for public recreation.

The law even took special notice of us, that is, the readers of the future, as it commanded the parks left “unimpaired for the enjoyment of future generations.”

Today, the parks remain with us—though they face an unprecedented threat in the form of climate change. President Obama even expanded the system this week, adding the Katahdin Woods and Waters in Maine as a National Monument (they are possibly the last wilderness on the East Coast that will receive protection);  and protecting more than 500,000 square miles of ocean off the coast of Hawaii.

But this is all a sideshow to the nice thing happening. Modern-day Americans—those “future generations,” dreamed of 100 years ago—still seem to appreciate the parks. All throughout this week, I’ve seen friends and strangers posting their own photos of the national parks to their Facebook and Instagram profiles under the tag #nps100. Instagram says more than 150,000 posts have gone up under the tag, and I’ve been enjoying scrolling through them.

Most of the photos aren’t professional, not all of them are in focus, and not all of the uncles or step-sisters pictured look exhilarated. But it’s been delightful, and surprisingly pleasant, and refreshingly organic-feeling (even if the NPS has been promoting the hashtag on its own materials all year)—this moment of collective gratitude for the parks, for the beauty that they contain, and for the decision to conserve them five score ago. However toxic or riven American public life has felt this year—however many real problems the National Park Service faces—there are still some goods that we pride ourselves on keeping in common.

The National Park Service has made it free to visit the parks through this Sunday, August 28. (Many sites are free already.)

At the top of this post, I said that this is the last Friday of the summer, but that’s only true by some definitions: There is one more Friday remaining in Unofficial American Summer (which ends on Labor Day, September 5), and three more Fridays in Astronomical Summer (which ends on the autumnal equinox, September 22). Go and enjoy them—possibly by visiting a national park.

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