Looking for a nice, long bike ride to stretch out your legs this summer? Sign up for the 465-mile Cycle Greater Yellowstone ride.

Big Bend National Park and the Rio Grande Wild and Scenic River claim 245 miles of this renowned river. And while many of those miles wend their way through rugged and remote canyon country, sections of the river nevertheless are on the state of Texas’ list of impaired water bodies. The primary concern is high total dissolved solids (high salinity), but bacteria can be a problem in the very upper reach.

Riptides along Cape Hatteras National Seashore are some of the most dangerous along the East Coast, but budget woes have left the question of whether there will be lifeguards on the seashore this summer up in the air.

A swarm of earthquakes, with one registering a 4.8 magnitude, shuddered parts of Yellowstone National Park on Sunday, with smaller quakes before and after that one reported by seismologists.