The city also retains a vast variety of Roman and Byzantine monuments, as well as a smaller number of remaining Ottoman monuments projecting the city's long history across the centuries. Athens is home to two UNESCO World Heritage Sites, the Acropolis of Athens and the medieval Daphni Monastery. Landmarks of the modern era, dating back to the establishment of Athens as the capital of the independent Greek state in 1833, include the Hellenic Parliament (19th century) and the Athens Trilogy consisting of the National Library of Greece, the Athens University and the Academy of Athens.
Athens has been continuously inhabited for at least 7000 years. By 1400 BC the settlement had become an important centre of the Mycenaean civilization and the Acropolis was the site of a major Mycenaean fortress whose remains can be recognised from sections of the characteristic Cyclopean walls. Unlike other Mycenaean centers, such as Mycenae and Pylos, it is not known whether Athens suffered destruction in about 1200 BC, an event often attributed to a Dorian invasion, and the Athenians always maintained that they were "pure" Ionians with no Dorian element. However, Athens, like many other Bronze Age settlements, went into economic decline for around 150 years following this.
Iron Age burials, in the Kerameikos and other locations, are often richly provided for and demonstrate that from 900 BC onwards Athens was one of the leading centers of trade and prosperity in the region. The leading position of Athens may well have resulted from its central location in the Greek world, its secure stronghold on the Acropolis and its access to the sea, which gave it a natural advantage over inland rivals such as Thebes and Sparta.
By the 6th century BC, widespread social unrest led to the reforms of Solon. These would pave the way for the eventual introduction of democracy by Cleisthenes in 508 BC. Athens had by this time become a significant naval power with a large fleet, and helped the rebellion of the Ionian cities against Persian rule.
Some of the neo-classical structures to be found are public buildings erected during the mid-19th century, under the guidance of Theophil Freiherr von Hansen and Ernst Ziller, and include the Athens Academy, Athens City Hall, Greek Parliament, Old Parliament (1875–1932) (Now the National Historical Museum), University of Athens, and Zappeion Hall.
Beginning in the 1930s, the International style and other architectural movements such as Bauhaus and Art Deco began to exert an influence on almost all Greek architects, and many buildings both public and private were constructed in accordance with these styles. Localities with a great number of such buildings include Kolonaki, and some areas of the centre of the city; neighbourhoods developed in this period include Kypseli.
In the 1950s and 1960s during the vast extension and development of Athens, modern architecture played a very important role. The centre of Athens was largely rebuilt, leading to the demolition of a number of neoclassical buildings.
- Omonoia Square, (Greek: is the oldest square in Athens. It is surrounded by hotels and fast food outlets, and contains a train station used by the Athens Metro and the Ilektrikos, appropriately named Omonoia Station. The square often becomes the focus for celebration of sporting victories, as seen after the country's winning of the Euro 2004 and the Eurobasket 2005 tournaments.
- Metaxourgeio (Greek: Μεταξουργείο) is a neighborhood of Athens, Greece. The neighborhood is located south of the historical center of Athens, between Kolonos to the east and Kerameikos to the west, and north of Gazi. Metaxourgeio is frequently described as a transition neighborhood. After a long period of abandonment in the late 20th century, the area is acquiring a reputation as an artistic and fashionable neighborhood due to the opening of many art galleries, museums, and trendy restaurants and cafes. Moreover, local efforts to beautify and invigorate the neighborhood have reinforced a budding sense of community and artistic expression.
National Park is punctuated by well-marked paths, gorges, springs, torrents and caves dotting the protected area. Hiking and mountain-biking in all four mountains remain popular outdoor activities for many residents of the city. The National Garden of Athens was completed in 1840 and is a green refuge of 15.5 hectares in the center of the Greek capital. It is to be found between the Parliament and Zappeion buildings, the latter of which maintains its own garden of seven hectares.
Parts of the city centre have been redeveloped under a masterplan called the Unification of Archeological Sites of Athens, which has also gathered funding from the EU to help enhance the project. The landmark Dionysiou Aeropagitou street has been pedestrianised, forming a scenic route. The route starts from the Temple of Olympian Zeus at Vasilissis Olgas Avenue, continues under the southern slopes of the Acropolis near Plaka, and finishes just beyond the Temple of Hephaestus in Thiseio.