The ancient city of Athens ceased to exist as a city and continued to decline until in Ottoman times it was nothing more than an Albanian settlement in the slopes of the hill. Here is an Ottoman engraving of the slopes of the Acropolis and surrounding area showing how abandoned and bare the region was.
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After the Greek uprising of 1821 a small area of present day Greece was freed from the Ottoman. The Great Powers assigned prince Otto of the Bavarian royal house to be king of the newly created kingdom of Greece.
At the time the capital was located in Nafplia (Nafplion) in the Peloponnesus. Young king Otto decided due to the historic nature of ancient Athens he would have the capital moved to the area around the acropolis. As a consequence he brought in surveyors from Bavaria and Europe and a new city was to be laid out and built as his new capital.
Thus, Athens was resurrected from the ashes of history and a new Athens -- discontinuous from the ancient Greek city -- was built under his orders. This is why you can't find older districts in Athens as you would in other European cities.
The old buildings in Athens -- other than the ancient ruins are almost all neo-classical in style, such as the parliament house (the old palace), the university, the academy and national museum. These buldings date from the 1830s onward.
Here is a photograph of the same area as the engraving showing how much development had taken place in new Athens. After the Greek fiasco in Asia Minor (1922) hundreds of thousands if not over a million Christian refugees were settled in new Athens. The city went from a population of a few thousand (5000 - 10000, mostly Albanians) in the early 1800s to five million 'Greeks' today. These would be Modern Greeks of course.
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Below is an engraving showing the Albanian community that lived among the ruins atop the Acropolis.
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A side view of the Acropolis through the gate:
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At the bottom of the following image you can see the plaka district -- which is the oldest section of new Athens. These are the remnants of the pre-existing settlement. You can see how the new city was developed beyond this poing. Most of the old settlement in the plaka was torn down for archaeological excavations.
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Here is an image of the famous Pnyx -- where the orator Demosthenes would have railed against the barbarian Philip of Macedon.
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Here is an engraving emperor Hadrian's Arch that led to the Roman part of Athens.
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Here is the same area after development. Athens Pic 8
More pics:
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More pictures of Athens -- showing the Ottomans using the area around the Acropolis to train their horses inside the Dionysos Theatre.
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Some more engravings:
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You can see the development of the Modern city as seen from the Acropolis.
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Here is an actual photograph of the Theatre of Dionysos where the Ottomans would train there horses. The area around the theatre is still undeveloped.
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You can see the new city of Athens being developed beyond the ruins of the Acropolis.
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Top left: Remnants of the Albanian settlement on the slope of the Acropolis. Bottom right, Cottages of construction workers. The area is called anafiotika because many of the workers came from the island of Anafi in the Aegean to help build king Otto's new capital
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Here is an interesting set of pictures showing how the old settlement on the slope of the Acropolis had incorporated the ancient ruins. Later, once the settlement was dismantled you can see the ruins standing alone.
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Picture source: Ancient Athens by John Miliadis:
Miliades Cover
Miliades Inside Cover