10 Fascinating Places for Urban Explorers

"Urban exploration" means discovering and investigating abandoned urban locations. These secret places are often forgotten, always interesting, and offer a unique window onto the history of a neighborhood or a city. The rush of exploring a place that may have been untouched for years is a sort of thrilling, unsanctioned sightseeing that even seasoned locals may not have experienced. Urban explorers are notoriously secretive about the best locations, so online information can be hard to find. After scouring forums and blogs, Cheapism.com turned up 10 intriguing, abandoned sites that each offer something special, be it history, art, or natural beauty.

Most urban explorers don't condone trespassing in places where it is explicitly forbidden. All the spots highlighted here are either freely open to the public or are so overlooked that no one has bothered to prohibit visitors. But you can always ask the property owner for permission to explore; WebUrbanist suggests contacting the local government to learn who owns the site. Be sure to follow standard urban explorer protocol: Be safe, never go alone, and leave things as you found them.

Hidden underneath Riverside Park on the west side of Manhattan lies an unusual art gallery. The walls of an Amtrak train tunnel display striking murals by famous graffiti artists. Spotlighted by sunlight filtering through the grates from the sidewalks above, many of the murals are now 25 years old. A common motif is the turbulent history of the so-called Freedom Tunnel, once a haven for a population of hundreds (some sources say thousands) of the city's homeless people. The tunnel was originally built in the 1930s but fell into disuse after 1980. By the mid-1990s, a shanty town had arisen inside the space, which also flourished as a site for street artists. When the tunnel was reopened for use by Amtrak, the tent city was bulldozed and the area chained off, and many of the murals mourn the loss of the underground community. Beginning in 2009, Amtrak started repainting the tunnels, and quite a few murals have been covered up. Street art aficionados and urban explorers should visit before it's too late.

The surreal back story of Murphy Ranch features a bizarre cast of characters including a wealthy steel heiress and a charismatic German national rumored to have had supernatural powers. These World War II-era ruins, secluded in the Santa Monica Mountains near Los Angeles, are all that remain of the compound built by a group of Nazi sympathizers. In the 1930s, the group spent $4 million constructing what was to be a self-sufficient command center for the Nazi movement in the United States. Money ran out and construction was halted before the project was finished. Federal agents stormed the ranch in December, 1941. Stone buildings, huge cisterns, and other ruins are all that's left, now rainbow-colored with graffiti. An easy four-mile hike along the Sullivan Ridge Fire Road to the ranch's location in Rustic Canyon, the site is open for exploration.

Just south of downtown Miami, seeming to rise straight up out of the ocean, are 6,566 stadium seats underneath a 326-foot roof. Built in 1963, the Miami Marine Stadium was the first stadium for powerboat racing in the country. In its heyday, it was the site for a number of well-known sporting and entertainment events, but in 1992, in the wake of Hurricane Andrew, it was declared unsafe for the public. Since then, the unusual site has become a playground for parkour (physical movements intended to get the practitioner from one point to another as efficiently as possible) and a canvas for eye-catching, candy-colored graffiti. The facilities may have lost their former elegance but the sweeping views of downtown Miami, Miami Beach, and the barrier islands have only become more breathtaking.

The early years of the city of Seattle were plagued by constant flooding, mudslides, and the Seattle Fire of 1889. When the city began to rebuild and expand into the metropolis it has become, it did so right on top of what came before. The result is a skeleton of the old city buried underfoot. Abandoned tunnels criss-cross beneath the city and are ripe for exploration by anyone with a flashlight and a sense of adventure.

Griffith Park is a favorite destination for Angelenos and tourists alike. But most don't realize that hidden in the park is the old Los Angeles Zoo (also called Griffith Park Zoo), which operated from 1912 until 1966, when the attraction relocated to its current location two miles away. The old zoo held just 15 animals and by the time it closed it had become the target of criticism for the small enclosures. The old cages and stone exhibits are still there as a reminder of how much animal welfare standards have changed over the decades. One stone exhibit is recognizable as the backdrop for the bear scenes at the San Diego Zoo in the movie "Anchorman." When you're done climbing around on the cages, find the cluster of picnic tables for an offbeat lunch spot. There are a few coal grills and a nearby playground, and the site boasts the beautiful city views that Griffith Park is known for. For extra spectacular views, hike up Bee Rock, a hive-shaped outcropping on the ridge to the west of the old zoo. The abandoned site is open to the public and reasonably well marked with signs pointing the way.

This is the only site on the list that displays no noticeable graffiti art -- whether this is because of faith, respect, or coincidence is anyone's guess. Built in 1933, the church was once a pillar of Cleveland's Slavic community. It represents the Byzantine Revival architectural style and, because of the Slavic influence, shows some Eastern Orthodox influences despite being a Catholic church. As neighborhood demographics shifted during the 1970s, the Slavic community dwindled and St. Joseph struggled with fewer than 100 members. The building was handed over to the Greater Zion Hill Baptist Church, a mostly black congregation. It has been abandoned since sometime in the early 2000s. The stained glass windows and the pews have been removed and the flooring was torn up for scrap, but the striking architecture of the structure can still be appreciated. The loveliest and best-preserved of the religious murals is on the ceiling above the main altar, depicting the Christ child surrounded by Mary, Joseph, and other biblical figures.

In the 1920s, the Portola district of San Francisco grew nearly all the flowers in the city, with at least 19 different nurseries tended mostly by Jewish and Italian immigrants. The University Mound Nursery is all that remains. It formerly occupied multiple city blocks with fields of flowers, but is now dotted with the old whitewashed wooden frames of the greenhouses. Although no longer tended, roses continue to grow wild through the ruins, prompting locals to nickname the site the Rose Factory. The city of San Francisco has considered purchasing the land and turning it into a park, but for now it remains a curious abandoned site. Enjoy the charming overgrown wooden frames and the gorgeous rose blooms.

The skeletons of the Zydeco Scream and other once-popular rides now tower forlornly over a wasteland of cement and weeds. Formerly Jazzland, then Six Flags New Orleans, the park closed for renovations just before Hurricane Katrina. Massive flooding and damage sustained during the disaster derailed any plans for development, and the park has sat empty ever since. With 224 acres to explore, there are plenty of interesting nooks and crannies to discover, from concession stands to old rides to torn banners flapping in the breeze.

Most of the cosmopolitan crowds and bustling pedestrians in the fashionable Washington, D.C. neighborhood of DuPont Circle neighborhood don't realize that just 25 feet below echoes a ghostly abandoned streetcar station. Built in 1949, the 75,000 square feet of white-tiled tunnels have been unused since 1962. They are eerily empty except for the fake trolley facades of the DuPont Down Under food court, a controversial and short-lived project back in 1996. This is a perfect example of a city's secrets hidden just below the surface.

Detroit is an urban explorer's paradise, with scores of abandoned sites in various stages of deterioration all over the sprawling city -- sometimes entire city blocks crumbling from disuse. Southwestern High School was abandoned only recently and is remarkably intact compared with others highlighted here, giving it an even eerier vibe. The school opened in 1916 in a growing manufacturing district; enrollment peaked in the 1940s with about 2,000 students, many from Hungarian families. With the closing of the nearby Cadillac auto plant in the 1980s, the neighborhood soon became emblematic of a once-booming city's downward spiral. In July, 2012, with only 583 students, the school closed permanently. The leftover furniture and supplies were auctioned online, and unsold items were left behind, which contributes to the unsettling vibe. Notes are still clearly written on chalkboards, basketball jerseys litter locker room floors, and the plush auditorium seats still look ready to welcome an assembly of students. This unique urban exploration experience may soon disappear -- rumor has it the site has been purchased by an India-based auto supplier and construction will commence this year.