Formalities have been taken to officially make Glacier National Park in Montana and Killarney National Park in County Kerry, Ireland, sister parks.

How big is too big for a national monument designated by a president? That has been an unanswerable question, legally, for some years, but a U.S. Supreme Court decision declining to hear a challenge to the designation of Northeast Canyons and Seamounts National Monument off the East Coast could move us closer to an answer.

It is one of the most magical, and demanding, backcountry treks you can make in the National Park System east of the Mississippi. For a week or more you can leave civilization behind as you explore Everglades National Park by canoe or sea kayak along the Wilderness Waterway, which turns 40 this year.

A sea of scorched Joshua trees, reduced to black skeletons of their former selves, darkens eastern California’s Mojave National Preserve. The pungent smell of their charred remains lingers even after January snowfall.