Tyresta National Park

Typically August 28–September 10

Sweden's most demanding national park has no marked trails, no bridges, and no huts, just 1,970 square kilometers of glacier-hung peaks and the braided delta of the Rapa Valley. Dwarf birch and willow on the tundra turn first, often by late August, with taller subalpine birch following into September as the first snow dusts Sarektjåkkå's 2,089-meter summit.

Don’t miss: Rapa Valley's braided delta · Sarektjåkkå, Sweden's second-highest peak · no marked trails or bridges

Pine trees several hundred years old cover this rocky ridge between lakes Vänern and Vättern, split by rift valleys jammed with glacial boulders the size of houses. Swedish folklore held the forest sheltered trolls and outlaws hiding from the law; 34 kilometers of marked trail now wind through birch, aspen and rowan that color through October.

Don’t miss: old-growth pine forest never logged · boulder-choked rift valleys · 34 km of marked trails

Typically September 4–September 21

Njupeskär's 93-meter drop, Sweden's tallest waterfall, cuts through a gorge below a birch-covered plateau in northern Dalarna. Mountain birch clinging to the rock, some barely shrub height and bent by wind, turns gold and rust through September; nearby grows Old Tjikko, a roughly 9,550-year-old spruce considered one of the world's oldest living trees.

Don’t miss: Njupeskär, Sweden's tallest waterfall · Old Tjikko, a 9,550-year-old spruce · wind-stunted mountain birch plateau