Although a trip to Mars remains a distant possibility for most of us, why voyage to the heavens when our own blue planet teems with otherworldly wonders? These breathtakingly surreal landscapes inspire our imagination and curiosity. And the "alien" creatures that inhabit them seem to defy nature itself, surviving and even flourishing in extreme conditions. With just the right mixture of minerals, microorganisms, temperatures, and of course, time, even regular old Earth is capable of some far-out creations.

Spewing scalding water in all directions, the aptly named Fly Geyser sits about 10 miles from the site of Burning Man, the annual counterculture art festival in Nevada's Black Rock Desert. This geological curiosity was formed accidentally in 1916, when ranch owners drilled a well in the area. They hit water, all right—too bad it measured a piping 200 degrees. The drilling crew plugged the well, but the geothermal water seeped through, leaving behind calcium carbonate deposits that continue to accumulate, forming a 12-foot-high bulbous mound resembling a scoop of rainbow sherbet.

In 1964, a crew drilled a second hole near the first, and once again found hot water, which this time erupted from multiple spots. The tie-dye stains dripping down Fly Geyer's surface are actually thermophilic algae, which thrive in hot, moist environments. Fly Geyser is off-limits to the public, but a Burning Man project director hopes to purchase its ranch land location to develop into an art park and idea incubator, mainly for the development of green technologies.

Blood Falls' grisly appearance comes from its iron-laden waters, which rust when they come in contact with the air, reddening the briny outflow as it trickles down Taylor Glacier onto ice-covered West Lake Bonney. What makes Blood Falls truly bizarre, though, are the roughly 17 microbial species trapped beneath Taylor Glacier, sans light or nutrients and with almost zero oxygen. Geomicrobiologist Jill Mikucki, now at Dartmouth College, has posited that the microbes rely on a metabolic process never before observed in nature: using sulfate as a catalyst to "breathe" with ferric iron and draw energy from nearby trace organic matter. 

At first glance, California's Mono Lake seems eerily barren. Twisting limestone pinnacles, called tufa towers, line its shores, some reaching heights of over 30 feet. Tufa towers grow only underwater, but Los Angeles' diversion of Mono Lake's tributary streams beginning in 1941 exposed the gnarled formations. Mono Lake, which is at least 760,000 years old, has no outlet to the ocean, causing salt to accumulate and create harsh alkaline conditions. Yet, oddly enough, Mono Lake hosts a flourishing ecosystem based on tiny brine shrimp, which feed the more than 2 million migratory birds that nest there each year.

In 2010, NASA astrobiologist Felisa Wolfe-Simon reported discovering bacteria in Mono Lake's arsenic sediments that could incorporate the toxic element into their DNA instead of phosphorous, normally a key building block of the double helix. For the most part, the new species' weirdness survived the scrutiny of two 2012 studies that debunked Wolfe-Simon's findings. Their conclusion? Mono Lake's "alien" bacteria do need phosphorous, but at surprisingly low amounts.

Northern Ireland's only UNESCO World Heritage Site consists of some 40,000 hexagonal basalt columns, which jut from the North Channel along the edge of the Antrim Plateau. Legend has it that the Irish giant Finn McCool built the causeway across the channel so that he could meet his foe, the Scottish giant Benandonner, who had challenged him to a fight. According to geological studies, the Giant's Causeway first formed as a lava plateau when molten rock erupted through fissures in the earth. During a period of intense volcanic activity about 50 to 60 million years ago, differences in the lava cooling rate caused the columns to form, while further weathering created circular formations nicknamed "giant's eyes."

Despite modern science's explanation, visitors still delight in the local lore. If you look closely, you can make out traces of Finn McCool in the causeway's rock structures such as the Giant's Boot, the Wishing Chair, and the Organ. 

Lake Hillier sits like a giant punchbowl at the edge of Middle Island in Western Australia's Recherche Archipelago, surrounded by a thick forest of paperbark and eucalyptus trees. A slender strip of shore separates Lake Hillier from the predictably blue Southern Ocean, highlighting the lake's otherworldly appearance.

Theories differ on the origins of the lake's bubblegum hue. Some believe it comes from a dye produced by two microorganisms calledHalobacteria and Dunaliella salina, while others suspect the red halophilic bacteria that thrive in the lake's salt deposits. In any case, the lake's color isn't a trick of the light—it's positively pink, no matter where you look. 

Years of erosion by vegetation and expanding ice carved Zhangjiajie National Park's narrow, terraced sandstone pillars, some of which climb over 650 feet. The park's steep cliffs and plunging gullies also make the perfect home for more than 100 vertebrate species, including scaly anteaters, giant salamanders, and sprightly rhesus monkeys. Meanwhile, the damp subtropical climate nourishes diverse, sometimes unusual, flora. Take dove trees, for instance.

Known as "living fossils," the white-flowered trees are actually survivors of the fourth glacial period 2.5 million years ago. Zhangjiajie National Park—China's first national park—is one of many within the Wulingyuan Scenic and Historic Interest Area in Hunan Province, named a UNESCO World Heritage site in 1992. 

Like Mono Lake 1,000 miles south, British Columbia's Spotted Lake is landlocked, resulting in salty, alkaline waters. Over the summer, much of the water dries, leaving behind a lava lamp pattern of mineral "spots" that can appear white, pale yellow, green, or blue, depending on their composition. These mini-islands consist mostly of magnesium sulfate, which crystallizes to form grayish walkways around and between the spots.

Spotted Lake also has a spotted history. The First Nations tribes of the Okanagan Valley have long viewed the lake as sacred. After World War I, the Ernest Smith family assumed control of the area and in 1979 tried to raise interest in building a lakeside spa. After a long struggle to buy the lake, the First Nations finally purchased 54 acres 12 years ago. Though the lake is fenced off, it is visible from the highway. 

The smallest of Yellowstone's geyser basins, Midway Geyser Basin (also dubbed "Hell's Half Acre") actually contains two of the park's largest hydrothermal features: Grand Prismatic Spring and Excelsior Geyser, which dumps 4,000 gallons of water a minute into neighboring Firehole River. The spring's psychedelic coloration comes from pigmented bacteria in the surrounding microbial mats. The amount of color in the mats depends on the water temperature and the ratio of chlorophyll (green pigment) to carotenoids (yellow to red pigment). In the summer, the mats burn orange and red, while winter turns them a dark green. The spring's lurid blue "eye" remains sterile because of its extremely high heat. 

Named after the Hawaiian word for "spewing," the mythical home of the volcanic goddess Pele rises 4,190 feet from the southeastern part of the Big Island. One of the world's most active and perilous volcanoes, Kilauea has been erupting for more than three decades, fitfully coughing basaltic lava into the Pacific Ocean below. You can easily spot the billowing plumes of scorching gas in the daytime. But if you can, visit after sunset, when the lava flows glow more visibly, creating a beautifully infernal light show. 

These Chocolate Hills won't satisfy your sweet tooth, although they might whet your curiosity. Measuring up to 400 feet tall, the hills are made of limestone containing marine fossils dating back millions of years. The verdant grass that usually covers the hills turns a milky brown come dry season, giving the more than 1,200 mounds their famously delectable appearance. The hills' origins remain a mystery, but legend says that a giant wept them as he grieved the death of his human beloved. Unfortunately, limestone quarrying has leveled some of the hills, a problem the Philippine government began addressing in 2006 by restricting mining activities in the area. Today, the confectionary landscape remains a popular tourist attraction and awaits approval as a UNESCO World Heritage Monument.