Forests and mountains

Monteverde Cloud Forest, Costa Rica
No, it's not a forest of clouds. Monteverde Cloud Forest got its name from the low-hanging fog that rests amongst the upper canopy of the forest. This fog offers some much-needed condensation to give the many plants a drink every day. This forest is particularly well-known for its excellent biodiversity, with 3,000 species of plants and over 100 different mammal species, 400 types of birds, and thousands of insect species.
Hallerbos Forest, Belgium
Sometimes, you don't just visit the forest for the trees. The Hallerbos Forest is particularly known for its thick blanket of bluebell flowers that bloom in the spring, making this forest completely enchanting –– almost like a fairy tale. Honestly, it's not hard to imagine Sleeping Beauty communing and singing with her animal friends in this place. If you visit Brussels in the spring, it's quite easy to visit the forest, but it's also a very popular tourist attraction, so you're likely to run into crowds.
Black Forest, Germany
No, Black Forest cake is not named after this beautiful forest. In fact, it's not even entirely black; it's actually quite green with its thousands of pine trees. Although the trees themselves aren't black, the forest gets its name because the evergreens are so thickly dispersed that the canopy blocks out a lot of daylight. So, even if it's a sunny day, you'll practically always be in the shade when you're there. The forest also has a number of quaint villages and natural thermal springs throughout.
Wistman's Wood, England
If you've ever dreamed of living in the Lord of the Rings or Game of Thrones universes, this forest comes awfully close. This forest, located in Dartmoor National Park, is home to plenty of tangled, moss-covered trees that look like they belong in a fantasy book. And the trees themselves are rooted in history, with some of the forest dating back to 7,000 B.C. and some of the larger oaks estimated to be about 500 years old.