The last place you'd expect to find a 10,000 SF (1,000 square metres) farm is below the business distract of Japan. The facility is called Pasona 02 was built in an former bank vault underneath a major Tokyo office building in the heart of the business district of Japan. The farm is broken up into 6 different rooms each with computer controlled temperature and lighting.
The facility grows everything from tomatoes, lettuces, strawberries to flowers and herbs. Around 100 different types of produce all up. There is also a paddy field used to grow rice.
In the absence of sunlight, the plants are sustained by artificial light from light-emitting diodes, metal halide lamps, and high-pressure sodium vapor lamps. The temperature of the room is controlled by computer, and the vegetables are grown by a pesticide-free method in which fertilizer and carbon dioxide are delivered by spraying. Hydroponics, in which plants are grown in water and hardly any soil is used, is one of the methods of cultivation used in the facility.
The farm is an initiative of the
Pesona Group company which also runs traditional farms among many other things.
It's goal is to create job opportunities in the agricultural sector.
This urban agricultural training facility focus on former "freeters" (Japanese young people who hop between part-time jobs) with an interest in farming. Through its Agriculture Internship Project in the village of Ogata, Akita Prefecture, Pasona, along with Kanto Employment Organization Inc, offered on-the-job training on a real farm. About 100 aspiring farmers, including young people and middle-aged businessmen, have already taken a course of agricultural training in Ogata. The whole training involves the possibility to receive initiation in farmings skills up to an Agri-MBA within the same the project.
The facility in Tokyo is open to the public until 6 p.m. to enable businessmen and office workers to drop by and experience hi-tech farming on their way home from work. It's also a unique tourist attraction worthy of a visit.
There's even a cafe to refresh yourself after a hard days work on the underground farm.
Official site here (Japanese) and
more info here.
The farm itself reminds me of all the space farms seen in sci-fi movies.
Dating back to Roman times the Catacombs of Paris is one of the most surreal experiences you can take while on a tour of Paris. For as little as $3 euro you can walk the 2 km (1.2 miles) of tunnels that are literally lined with human bones from some six million Parisians.
As the Paris population grew in the 1700's the number of cemeteries didn't. As disease spread due to improper and cramped burials the police chief decided to condemn all the inner city cemeteries and move the remains discreetly to a renovated section of Paris' abandoned quarries.
The catacombs isn't just skulls and bones. There is also the occasional open area.
The actual tunnels stretch for hundreds of miles underground only a tiny portion is open to the public. It's an offense to venture into the unsupervised areas. The map below shows the full extent of the tunnels.
Fun Fact: In 2004 a secret cinema was discovered by police who stumbled upon the make shift cinema complete with projection screen and seating by accident during a training exercise.
You can also visit the Catacombs of Rome which contains artwork dating back to 400 AD.
You can also visit the 
The secret is out. The former U.S. Government Relocation Facility is now open. Explore the 112,000-square foot hideaway beneath 
The site remained a top level secret until 1992 when the Washington Post published an article titled "The Ultimate Congressional Hideaway". 
The broadcast center (below) had backdrops to make it appear members of Congress were actually broadcasting from Washington, D.C., by changing the backdrop for each season-- a 100-foot radio tower was installed some miles away for these broadcasts.
The facility was built over 3 years from 1959 and 1962 and as you can see below the computer hardware hasn't changed much since.
Here's the current secret entrance used for daily tours of the facility.
Visit the 
