The Seven Wonders of the World are famous, but what about those that didn't quite make the cut? Take our word for it—they are just as worth seeing. But visits to some of these marvels need to be timed just right, as they only happen a few months out of the year. Whether it's a special chemical reaction or a synchronized mating ritual, these splendors deserving a spot in your schedule. In every corner of the world, Mother Nature has something up her sleeve that continues to shock visitors year after year.
Lake Abraham, Alberta, Canada
Each winter, as this lake begins to freeze over, what happens under the surface is much more curious than what meets the eye. Bubbles of methane form on the floor of the lake throughout the year and as the temperatures drop, the orbs rise and freeze at various heights in the water. These beautiful patterns can be dangerous though; if a bubble cracks, highly flammable gas is released.
Synchronous Fireflies, Great Smoky Mountains, Tennessee and North Carolina
Did you see that? In a rare occurrence of non-human life working in mysterious ways, thousands of fireflies gather together and flash simultaneously every few seconds during their mating ritual, which lasts for only two weeks a year, usually sometime during May or June.
Caño Cristales, Meta, Colombia
During part of the year, red algae flowers make this river in the National Park of La Macarena shine a vibrant, ruby-red color. The peak time to see the colors in full form are late summer to early autumn.
Catatumbo Lightning, Maracaibo, Venezuela
Where the Catatumbo River meets Lake Maracaibo, lightning does, in fact, strike twice. It has been known to flash up to 250 times per square kilometer (.4 mile) per year, leading to up to 300 storm days annually, with the best time for viewing June through November. NASA says it is the highest concentration of lightning on earth.
Starling Murmuration, United Kingdom
In what mimics a dark cloud moving through the air every fall across the United Kingdom, onlookers can witness this amazing display of animals working in ways humans have yet to fully understand. Anywhere from hundreds to thousands of these birds group together, creating this synchronized dance in the sky.
Crooked Forest, Gryfino, Poland
What might appear to be a regular grove of trees from a distance is far from that upon closer inspection. Around 400 pine trees, each less than 100 years old, make up what is known as the "crooked forest" due to the inexplicable way each one developed with a crooked trunk at its base before straightening back up.
Sea of Stars, Vaadho, Maldives
The Maldives is known for its beautiful turquoise waters and bungalows, but what's going on just under the sea is at least as impressive. In the late summer, the reefs around the Maldives fill with bioluminescent phytoplankton; ignited by the movement of the waves, they make the water glow like a star-filled sky.
Kawah Ijen Crater, Java, Indonesia
While lava typically appears bright red or orange, due to a chemical reaction when sulfur meets the air at this volcano, the lava shines a bright blue color that is only really visible after sundown. Visiting this region is not for the faint of heart, though, due to the presence of toxic gases that make this act of nature possible—but also inhospitable to humans.
Nacreous Clouds, Antarctica
While these shimmering iridescent clouds visible mainly in the polar regions are eye-catching, they are in fact quite dangerous to the ozone layer. Occurring only at very high altitudes when the temperature drops enough to crystallize the moisture in the air, the light reflects off of these crystals to create a lustrous, mother-of-pearl effect—and a destructive chemical reaction.
