For prime biking, rafting, and other adventures, you can’t beat Montana’s Glacier National Park.

• 

  photograph by James C. Hayes/HAYES PHOTOS

  Glacier National Park’s Going-to-the-Sun Road offers magnificent views.
• 

  photograph from jay atkinson and john hearin

  Some parts of the park are accessible year-round, but most of the 13 campgrounds open in mid- to late May, depending on the weather.
• 

  Photograph by Rick Sammon/Associated Press/2002

  A mountain goat along the main road that runs through Glacier National Park near Kalispell, Montana.
• 

  photograph by DONNIE SEXTON/montana office of tourism

  The average high temperature is 57 degrees in April, 73 in June.
• 

  photograph by jay atkinson and john hearin

  The author and his group cycled 11 miles uphill on Going-to-the-Sun Road to where it was blocked by an avalanche.
• 

  photograph by jay atkinson and john hearin

  The Stillwater River, a tributary of the Yellowstone, was running high on snowmelt and churnin g up sediment.
• 

  photograph by DONNIE SEXTON/montana office of tourism

  A view of beargrass off Going-to-the-Sun Road.
• 

  photograph by jay atkinson and john hearin

  Mid-May is the sweetspot for Glacier National Park, as road repairs and avalanches can prohibit motorized traffic.
• 

  photograph by DONNIE SEXTON/montana office of tourism

  The forest occasionally gives way to dramatic views of nearby peaks.
• 

  photograph by DONNIE SEXTON/montana office of tourism

  Going-to-the-Sun Road meanders up and over the divide between Lake McDonald and St. Mary Lake (pictured).
• 

  Photograph by Jennifer demonte/the daily inter lake/associated press/2004

  A breathtaking view on the road less than 4 miles from Logan Pass.
• 

  Photograph by Rich Addicks for the new york times

  Highway 89 outside Browning, Montana, parallels the boundary between Glacier National Park and the Blackfeet Indian Reservation.
• 

  Photograph by Mike Albans/ASsociated press/file/2010

  Glacier National Park is known to Native Americans as the “Shining Mountains” and the “Backbone of the World,” according to the National Park Service.
• 

  photograph by lisa mckeon/us geological survey/associated press/file/2009

  The park is named for its prominent glacier-carved terrain and remnant glaciers descended from the ice ages of 10,000 years past.
• 

  photograph by rich addicks for the new york times

  In 1932 Glacier National Park and Waterton Lakes National Park, across the border in Canada, were designated Waterton-Glacier International Peace Park.
• 

  photograph by DONNIE SEXTON/montana office of tourism

  Glacier National Park’s diverse habitats are home to nearly 70 species of mammals.
• 

  photograph by DONNIE SEXTON/montana office of tourism

  Going-to-the-Sun Road has been dedicated as a national historic civil engineering landmark.