Introduction to Cavity Detection

Whether former mining tunnels, old shelters or burial chambers in temples, churches or pyramids, the search for cavities blurs the line between treasure hunting and archaeology. Discover the fascination of treasure hunting under special aspects: Cavity detection goes beyond finding magnificent gold treasures and artefacts: The search for cavities focuses on the discovery of underground vaults, tunnels or bunkers, which usually also contain overwhelming treasures and unexpected values.

Cavity Detection – Search for treasures of mankind

There are thousands of artifacts and valuables in underground caverns waiting to be discovered. What exactly can treasure hunters find and where are the most interesting kinds of cavities?

  • Caves:

    Naturally formed or man-made cavities in rocks or in the ground offer excellent hiding places for religious shrines with valuable artifacts or for prey from thieves and stagecoach robbers.


  • Tunnels:

    Connecting passages built by humans serve, for example, as access to special rooms or as secret escape tunnels. With their discovery, a piece of history of building complexes can be reconstructed.


  • Bunkers:

    The concrete shelters, which served as a military base or as part of defence lines, are of particular interest dating from the First and Second World War.


  • Arches:

    Old building structures, which served as living rooms, wine cellars, storerooms or workplaces, often contain artefacts that had been left behind. These valuable treasures allow conclusions to be drawn about the type of building.


  • Treasure chambers:

    Whether in castles and palaces or within the walls of places of worship, state treasures and church treasures were and are particularly carefully guarded in treasure chambers.


  • Grave chambers and tombs:

    Whether in pyramids or temples, the tombs of kings, dignitaries and rulers hold valuable treasures and artifacts.


  • Crypts:

    Relics for ceremonies are kept in the vaults under churches. Crypts also serve as burial places for dignitaries.

  • Catacombs:

    Deceased were buried in pre-Christian underground graves. Due to the increasing lack of space, the old tradition was rediscovered in some large cities, for example Jerusalem.


  • Sarcophagi:

    Large, magnificent coffins and sarcophagi made of stone or metal can be found in burial chambers in crypts, temples and pyramids. They serve as a final resting place for high-ranking personalities, who were usually buried together with valuables and riches.


  • Treasure chests:

    Treasure chests are also, in a certain sense, hollow spaces in which treasure hunters can find valuables. When examining treasure chests with OKM detectors, users should bear in mind that boxes may be made of iron or contain iron parts that influence the measurement results.


  • Galleries:

    Galleries and corridors with certain features – whether with arcades, surrounding an inner courtyard or connecting several rooms – provide an indication of the discovered type of building. The conclusion if it is a church, a castle or perhaps a theatre, allows further suggestions about the position of other interesting rooms such as burial chambers and treasure chambers.


  • Mines:

    Just like natural caves, abandoned mines are ideal hiding places for riches.


  • Ghost towns:

    In deserted places, so-called ghost towns, numerous artefacts and clues to the past can be found, especially when the town has been left and abandoned spontaneously. Find the treasures before the nature recovers the landscape!


Treasures of the Old World hidden in chambers and vaults

Treasures of the nobility such as the riches of the Wettins or the crown jewels of the British monarchy were and are still are kept in treasure chambers. The riches of the church were also hidden in vaults and crypts under chapels, churches and cathedrals.

The Cologne Cathedral (Germany), the Green Vault in Dresden (Germany), cathedral treasure chambers in Germany, Liechtenstein and Italy as well as the Tower of London (Great Britain) are just a few of the numerous treasure chambers in Central and Western Europe. Outside Central Europe, the treasures of the Topkapi Palace in Istanbul (Turkey) and the Moscow Kremlin (Russia) attract visitors. Many of the treasures are now part of the world cultural heritage and are partly open to the public.

Numerous hidden treasure chambers are still waiting to be discovered. Over the centuries, riches were hidden in underground vaults – sealed to protect them from plunderers or buried by natural events – and were forgotten gradually. Treasure hunters follow legendary myths and targeted clues with the aim of making the greatest find of their lives.

More about treasure hunting

Downtown: Lost places below the earth tell their stories

In order to create new living space and constantly improve the urban infrastructure, supply lines, underground tunnels and car parks are being built. It is not unusual for construction companies to come across old walls and vaults, which are of great interest to archaeologists, especially in city centres. With appropriate detection technology such as ground scanners and cavity detectors, these old tunnels, vaults, wells, cisterns and aqueducts can be discovered and located before civil engineering work begins.

The rediscovered cities of past centuries were covered or replaced in the course of time – some vaults continued to be used and remained intact, others have been forgotton at some point. Often the foundation walls, remains of buildings and galleries are well preserved and protect artefacts and treasures which wait to be rediscovered.

Wonders of Antiquity: Underground Rome (Italy)

Many stairs lead deep below the Italian capital into underground corridors, tunnels and churches, which have been under the metropolis for 2500 years.

Secret passages: The catacombs of Paris (France)

Since the Middle Ages limestone has been mined in the mysterious corridors. The galleries are several kilometres long and lie far below the sewerage system. At the end of the tunnels there are bones of six million people.
Not only the catacombs of Paris and Rome are underground “cities” of a special kind. In Jerusalem, the ancient tradition is being revived: Even today, new underground Jewish cemeteries are still built.

Complex connection between the Hasmonaean age and modernity: The tunnels under Jerusalem (Israel)

Under the impressive Wailing Wall there are tunnels leading along for about 448 metres. The complex underground tunnels were first discovered by British archaeologists in the 19th century. The actual excavations were carried out 100 years later by the Ministry of Religions.

Bunkers of Second World War: The Underworld of Berlin (Germany)

Under the world-famous Berlin, there is also an underground city: the “Underworld” houses an impressive protection bunker from the Second World War. The numerous corridors and rooms of the bunker complex resemble a labyrinth. Moreover, the Berlin sewage system is one of the oldest, best and largest in Europe.

Deep well: The underground labyrinth of Derinkuyu (Turkey)

In the Turkish region of Cappadocia there are underground cities, some of which date back to the 8th century BC. Derinkuyu is the largest and was probably built by the Hittites. The multi-storey labyrinth of ventilation shafts, wells and a wine cellar served 20,000 people as living space and refuge.

Roman and Greek Roots: Historical Roads under Naples (Italy)

About 40 m below ground there is an old city under the “new” city of Naples, which reminds of its Greek and Roman roots. The underground structures reveal paved streets, remains of an aqueduct, shop fronts and a Roman theatre.

The legendary underworld: South Bridge Vaults in Edinburgh (Scotland)

Not as ancient as the Roman walls or as old as the Paris catacombs, but still exciting and fascinating are the confusing passages under the South Bridge in Edinburgh. The chambers in the arches of the bridge were used in the 18th century as warehouses, workspaces and living quarters, but were closed in the middle of the 19th century and were forgotton. It was not before 1989 when the chambers filled with historical artefacts have been rediscovered.

Lost place at the foot of the volcano: Plymouth (Caribbean)

Unlike the previous cities, Plymouth, capital of the British overseas territory of Montserrat (Lesser Antilles), was afflicted by a force of nature: The volcano Soufrière Hills erupted several times between 1995 and 1997 and buried the buildings under 1.5 m ash masses.

The warship phantom island: Hashima (Japan)

160 m wide and 480 m long, this awesome concrete island rises out of the East China Sea. From the end of the 19th century to the middle of the 20th century, coal mining attracted tens of thousands of workers to the city, which is surrounded by metre-high protective walls to protect it from waves. Today, Hashima is an industrial monument.

Which underground bunkers, tunnels, treasure chambers, vaults or ghost towns are you going to discover?

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