In the past week, the discoveries of two very different and amazing underground temples were in the news. But they are not the only ones.

1. The Lupercale
Just last week, the first pictures of a recently-discovered underground grotto in Rome were released. The chamber is 26 feet high and 24 feet in diameter. The discovery was made about a year ago as workers were repairing the remains of Emperor Augustus' palace on the Palatine, a hill in Rome. Archaeologists believe it is the original Lupercale, the site where legend says the founders of Rome, Romulus and Remus, were nursed by a wolf after having been abandoned by their parents, the war god Mars and mortal priestess Rhea Silvia. The chamber is partly filled with debris, but the ceiling mosaic gives a glimpse of the majesty the temple had when it was in use 2,000 years ago.

2. The Temples of Damanhur
In 1978, Oberto Airaudi and a few friends began excavating the ground under the alpine hill in Italy on whch they lived. They dug for 16 years in secret, as they had no permit for the project. When authorities demanded to see the dig in 1992, they were astonished to find nine ornately-decorated chambers, with a total volume approaching 300,000 cubic feet! Although the Italian government seized the temples for a time and was going to destroy them, a retroactive permit was eventually issued. Airaudi (who prefers the name Falco) and his colleagues continue building the underground temples to this day, with plans for bigger and better underground chambers to come.

More on the Damanhur and other temples, after the jump.

Falco's organization, the Federation of Damanhur, runs tours of the Temples of Humankind complex, a two-day affair with a day of "preparation" and a day of viewing. The temples are not dedicated to any deity, but to humankind. They were built for meditation and spiritual renewal. See more photos of the temples of Humankind at the official website.

3. The Underground Temple at Hampi
The city of Hampi in Karnataka, India is a UNESCO World Heritage site as a grouping of Hindu monuments. One of these is the Underground Temple, believed to have been built in the 13th century and used until Muslim attacks left the city in ruins in the 16th century. This temple of Siva is underneath the water table, and the inner sanctum is usually flooded. However, tourists are welcome to go as far down the passageway as possible.

4. The Hypogeum at Hal Saflieni
The Hal Saflieni Hypogeum in Malta is a UNESCO World Heritage Site and the oldest underground temple we now know of. Its 500 square meters spread over three levels of halls, chambers, and passageways carved out between 3600 and 2500 BC. It was rediscovered in 1902 by a stonemason who was building houses over the temple. The Hypogeum is open to tourism, with a limit of 80 visitors a day, so reservations should be made far in advance. See more pictures at Malta Temples.

5. The Osireion
The Osireion is a false tomb connected to the Seti I temple at Abydos in Egypt. It is the mythical burial tomb of the ancient Egyptian god Osiris. Seti I reigned in the 13th century BC. The Osireion was built below the water table and was flooded much of the time before its 20th century excavation. It was discovered during an excavation in 1902, but not fully explored until 1926. Part of the Osireion is open to the surface now, but originally had limestone roofs below ground level. This photo by Ernesto Graf shows a section that is both exposed and flooded.