Peru's peak tourist season is from June to August, which is the dry season in the highlands, and this is the best time to go if you're interested in hiking. Travelers do visit the highlands year-round, though the wettest months, January to April, make trekking a muddy proposition. Many of the major fiestas occur in the wettest months and continue undiminished in spite of heavy rain.
On the coast, Peruvians visit the beaches during the sunny months from late December through March, although few beaches are particularly enticing. The rest of the year, the coast is clothed in mist. In the eastern rainforests, it naturally rains a lot. The wettest months are December through April, though travelers visit year-round since it rarely rains for more than a few hours and there's still plenty of sunshine to enjoy.
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