The North American and European tectonic plates meet in the Silfra Fissure within the UNESCO-listed Thingvellir National Park, located just east of Reykjavik in Iceland. You don’t have to admire the otherworldly geological features from afar: Don your wetsuit and snorkeling gear and swim through the protected underwater canyon where continents collide and the elusive Arctic char swim.

Hop on your eco-friendly, battery-powered electric bike and ride to the end of Ketchikan’s “Road to Nowhere,” an unfinished gravel highway that winds through the low forests and remote scrubland of southeastern Alaska. Then, trek through the protected wilderness and rainforest of the Tongass National Forest, where it’s not unusual to see salmon spawning in streams and dolphins, sea lions, and humpback whales breaching off the shoreline. This is what nature restoration travel is all about.

Endangered manatees feeding in estuaries, cuckoo birds calling from mangroves, and loggerhead turtles nesting on beaches—see all this and more in Florida’s Ten Thousand Islands National Wildlife Refuge, one of the largest expanses of mangrove forests in North America. This short wildlife conservation trip is long on wildlife encounters: Navigate through remote islets looking for manatees, dolphins, turtles, and eagles, and search for seashells on a remote island with a naturalist guide.

Among the world’s most intelligent (and endangered) sea creatures, magnificent manta rays are friendly to humans—and this tour lets you swim near them while they feed on plankton at night. Cruise to an ideal manta-viewing location at the mouth of Keauhou Bay near Kailua-Kona on the Big Island of Hawaii, get in the water with light-equipped flotation devices, and spotlight the rays as they barrel roll and turn in the water.

Carl Sagan famously called Earth a “pale blue dot” as seen from space—but you don’t have to travel that far to appreciate our planet. You can, for example, fly above the Alaskan wilderness and see Denali National Park from above. On this flightseeing tour, soar over some of the most remote rivers, valleys, and glaciers in the US—it’s a roughly 6-mile route from the Denali summit over the Ruth Glacier, the Great Gorge, Mount Huntington, the Moose's Tooth rock peak, and other geological wonders.

The only rain forest in the National Forest System, El Yunque National Forest has canopy walkways, dwarf forests, Indigenous petroglyphs, and—best of all—natural pools beckoning visitors to take a dip. Start this day-trip adventure by hiking to some of the forest’s most beautiful swimming spots; then, take a kayaking trip through mystic mangroves to bioluminescent Laguna Grande, where microscopic plankton produce natural light at the touch of your paddle.

Let’s keep the bioluminescent theme running with this off-the-beaten-track glowworm-caving adventure in Waitomo, New Zealand. Pull on your boots and helmets and dive headlong through the underground labyrinths, galleries, and grottos of Mangapu Gorge and Mangarongapu Cave, where millions of bright green glowworms illuminate the limestones. The resident species of glowworms, officially called Arachnocampa luminosa, are known worldwide but found exclusively in New Zealand.

According to official research, conservation efforts have helped the global humpback whale population rebound in recent decades. What better way to celebrate than by cruising out of Reykjavik’s Old Harbour to witness the giants breaching and swimming in Faxaflói Bay and along Iceland’s graceful coast? It’s easy to spot dolphins along the way, but the best part of this tour is the success rate for seeing whales: 95 percent in summer and 80 percent in winter.

Sometimes, one day is simply not enough to experience the wonders of the natural world. On this eco-tourism adventure, you’ll spend four days exploring the Tambopata National Reserve, a swathe of protected land. Fly in from Puerto Maldonado, cruise the Madre de Dios River, and anchor near the EcoAmazonia Lodge, where you’ll get to sleep for three nights. Spend the rest of your trip spotting wildlife on nearby islands, visiting local communities, exploring a Brazil nut plantation, and more.

It’s hard to find a natural wonder that inspires the imagination more than the northern lights. They’re notoriously elusive, but you can find them (relatively) easily enough if you have a good guide and travel during the right time—especially in Iceland. With this northern lights hunt, venture out into the countryside near Reykjavik after dark, stop at remote viewpoints according to the official forecasts, and sample Icelandic pastries and hot chocolate as you wait for the lights to appear.