Unique

Big Talbot has the strangest beach in Florida. The island is eroding, and as the bluff retreats it drops entire live oaks and cedars onto the sand below, where salt and sun bleach them white. The result is a shoreline of enormous pale driftwood skeletons, some still rooted, arranged along the tideline - it looks like nowhere else in the state and photographs extraordinarily well. Getting down means a short trail from the roadside parking and a scramble at the end. This is a walking and looking beach, not a swimming one: the water has current and there are no lifeguards.

This is the largest Anastasia limestone outcrop on the Atlantic coast, and when a high tide coincides with an onshore swell the sea funnels through blowholes in the rock and erupts in plumes that can reach fifty feet. It is genuinely spectacular and genuinely conditional - on a calm day at low tide you get an interesting rocky beach and nothing more. Check the tide chart and the swell before you go. The Nature Conservancy runs the preserve and there is a small visitor centre. Climbing on the rocks is dangerous when the surf is running, which is exactly when it is worth watching.

Devil’s Den is an underground spring inside a dry cave, reached by walking down a wooden staircase into the earth. Light comes through one hole in the roof and falls in a shaft across water that stays at 72 degrees, which on a cold morning makes the whole opening steam - hence the name. Snorkelling here is unlike anything else in Florida: you are floating in a rock room, not a river. It is privately run, reservations are required, and there is a hard minimum age with no swimming for small children. Book well ahead in season.

The Frederiksted pier is one of the most celebrated shore snorkels in the Caribbean, and what makes it special is not reef but structure: concrete pilings running down into sand, colonised by orange and purple sponge, with the strange creatures that come with that habitat - seahorses, juvenile drums, frogfish, octopus at dusk. The water is calm and clear on this leeward coast and mostly under twenty-five feet. It suits a child who is a strong swimmer and patient enough to look closely, more than a beginner. Access is from the beach beside the pier; cruise ship days close the water near it.

Laguna Grande is one of three bioluminescent bays in Puerto Rico and the one most families choose, because it is reached by a mangrove channel rather than open water and the tour operators run tandem kayaks with guides throughout. The dinoflagellates in the lagoon flash when disturbed, so your paddle blade, your hand in the water, and fish moving under the boat all glow. It genuinely works - but it depends on darkness, so tours only run around the new moon and are cancelled by a bright moon or heavy rain. The mangrove channel is narrow and requires steering, which is why the practical minimum age is around six.

Mosquito Bay holds the record for the brightest bioluminescence measured anywhere, and the difference from the mainland bays is obvious the moment you are on it: the water does not just sparkle, it lights up enough to see by, and fish moving beneath the boat draw glowing wakes. Swimming is prohibited in order to protect the organisms, so this is a paddle-only experience. Getting there means the Vieques ferry from Ceiba or a short flight, which turns the bay into a two-day trip rather than an evening. Tours are new-moon dependent. Book both the ferry and the tour well ahead.

Salt River Bay carries two distinct things at once. It is a national historic park because this is the single confirmed place where a Columbus landing party came ashore on territory that is now the United States, and it holds significant Taíno archaeology. It is also a bioluminescent bay, and guided night kayak tours run out into it around the new moon, when the dinoflagellates light up under the paddle. The mangrove estuary is protected and calm. Like every bio bay the experience is entirely moon and weather dependent, so book early in a trip to leave room to try again.

A barren, otherworldly landscape of wind-sculpted red rock formations and boulders that looks like the surface of Mars. Hawaiian legend says the rocks were placed here by the gods. The red, orange, and purple colors of the rock against the blue sky are striking, especially at sunrise and sunset when the light is warm. Kids love climbing on the rocks and the landscape is so unusual it sparks their imagination. A 4WD vehicle is needed to reach the site. Views of Molokai across the channel add to the drama. There are no facilities so bring everything you need.

Two stunning glacial lakes with impossibly blue-green water that looks like the Caribbean set in the woods of central New York. Green Lake and Round Lake are meromictic, meaning their layers never mix, which gives them their striking color. The beach on Green Lake has lifeguards and the water is refreshing on hot days. A 3-mile trail loops around Green Lake through beautiful forest. The park also has an 18-hole golf course, playground, and campground. The lake color alone makes this worth the visit.

Dramatic pointed clay spires rising over 150 feet above the shore of Lake Ontario, sculpted by wind, rain, and waves into shapes that look like something from another planet. The Bluff Trail along the rim gives top-down views of these formations while the Beach Trail offers a look from below. The formations are constantly changing and eroding so they look different every year. Kids are fascinated by the alien landscape. Stay on marked trails as the clay edges are unstable. It is genuinely one of the most unique natural sites in New York.

A short walk across a windswept point to a formation of sharp, jagged lava rock teeth jutting upward from the coastline that looks like a dragon rising from the earth. The rock formations were created by lava meeting the ocean and are unlike anything else on Maui. Kids are fascinated by the shapes and the crashing waves around the point add drama. An ancient Hawaiian labyrinth made of stones sits nearby. The walk is short and flat but the terrain is uneven lava so watch footing. Great whale watching spot in winter.

A unique snorkeling spot where warm water discharged from a nearby power plant attracts an incredible diversity of marine life. Spinner dolphins, sea turtles, eagle rays, and dense schools of fish are regularly seen in the warm outflow channel. The visibility is good and the marine life density is higher than almost anywhere else on Oahu. The entry is over rocks and there are no lifeguards so this is best for experienced swimmer families. When conditions are calm, the snorkeling is genuinely world-class and free.

Float through old sugar plantation irrigation ditches and tunnels hand-dug over a century ago on an inner tube. The gentle current carries you through 5 tunnels, some pitch black except for your headlamp. Kids love the tunnel sections where the only light is from their own headlamp reflecting on the water. The surrounding scenery is lush and green. The water is warm and the current does most of the work so it is relaxing and exciting at the same time. This is a uniquely Kauai experience you will not find anywhere else in Hawaii.

A short loop trail through a forest of eerie lava molds left behind when a lava flow swept through a forest of ohia trees in 1790. The trees burned away but the hardened lava preserved their shapes, creating hollow pillars and ghostly tree-shaped columns. Kids think the formations look like petrified forest creatures. The 0.7-mile paved loop is easy and shaded. It is a quick stop that vividly demonstrates the power of volcanic activity in a way kids can see and touch. The surrounding forest has regrown around the formations creating a beautiful contrast.

Snorkel with giant manta rays at night in one of the most unforgettable wildlife encounters in Hawaii. Operators set up surfboards with lights that attract plankton, which in turn attract manta rays with wingspans up to 12 feet that glide inches below you as they feed. Kids hold onto the lit surfboard and float face-down watching the graceful mantas do barrel rolls in the light. It sounds scary but the rays have no teeth or stingers and the experience is peaceful and awe-inspiring. This is a bucket-list Hawaii activity.

A mountain forest on the slopes of Haleakala at 6,200 feet that feels nothing like tropical Hawaii. Towering redwood, eucalyptus, and pine trees create a cool, misty forest that could be in the Pacific Northwest. The Redwood Trail and Plum Trail are family-friendly loops through these unusual forests. The temperature is 20 to 30 degrees cooler than the coast which surprises kids who expect Hawaii to always be hot. On clear days the views of Maui central valley and the ocean are spectacular. A cabin is available for overnight stays.

A unique landscape of dwarf pine barrens, ice caves, and dramatic cliff-top views on the highest point of the Shawangunk Ridge. Kids are fascinated by the ice caves, narrow rock passages where ice persists into summer. The loop trail to the caves is about 3 miles and the Verkeerderkill Falls overlook adds a spectacular waterfall view. The dwarf pine barrens at the top are globally rare and feel like another planet. This is one of the most unique hiking experiences in downstate New York.

One of only four green sand beaches in the world, located at the southernmost point of the United States. The green color comes from olivine crystals in the volcanic cinder cone that surrounds the beach. Reaching it requires a 5.5-mile round trip hike across windy grassland or arranging a local shuttle ride. The beach sits in a cinder cone amphitheater with dramatic cliffs and crashing waves. The green sand is genuinely remarkable and kids love collecting (and then returning) the tiny green crystals. Swimming is rough and not recommended.

The longest elevated pedestrian bridge in the world, a converted railroad bridge 212 feet above the Hudson River. The 1.28-mile walk across offers incredible views up and down the river and of the surrounding mountains. Kids love the experience of being that high above the water and the bridge is wide, flat, and fenced, making it safe for all ages. An elevator on the Poughkeepsie side makes it accessible. On the Highland side, the Walkway connects to a rail trail for extended biking and walking.

One of the only places in Texas where families can legally dig for and keep real fossils including 300-million-year-old marine specimens. Kids are thrilled to crack open rocks and find ancient crinoids, gastropods, and brachiopods that they can take home. No tools or experience are needed as the fossils are abundant in the exposed shale. This is a free outdoor activity that keeps kids engaged for hours.