After tirelessly following a series of wooden hand-painted signs, which insisted that the Acropolis was ahead, a small group of us were on the verge of abandoning our search for the site when we ran into our instructors, Lisa and Alex (Fig. 1). Amidst the maze of tiny plastered homes, we followed them through narrow whitewashed hallways accented with magenta rugs and royal blue planter beds until we passed through the marble entrance of the Acropolis. Through staggered breaths, we began to realize the magnitude of our own unique purpose and place.
In Flagstaff, Arizona, I surround myself with people who live a sustainable lifestyle, as I strive to do the same. Now, when I travel to new cities, states, or countries I am immediately drawn to their historical and modern sustainable efforts.
The first thing I noticed about Greece’s “upper city” was the marble it was constructed from. Beneath the Parthenon, the temple dedicated to the Greek goddess Athena, lays two fundamental rock types, Athenian Schist and limestone. The upper rock bed of limestone is sedimentary while the lower schist formation is metamorphic. We could tell right away that the basement layer was limestone from the color, hardness and presence of fossils in the rock (Fig. 2 & 3).
Marble is the metamorphic form of the aforementioned limestone. It is formed when limestone recrystallizes under extreme heat and pressure beneath the Earth’s surface. The non-vesicular nature of marble allows the rock to serve as a durable building material. Although calcium carbonate resides within marble, and can be “easily attacked by acidic agents,” it is still beneficial when used as a “factor in limiting and controlling the severity of exposure” .
Two notable hilltops reside in Athens, the lower of two was chosen to fortify the Acropolis for an array of reasons. The steep rock walls served as a natural fortress and hence did not allow for ease of access from either side. During the fortification of the Acropolis in the 13th Century BC, natural spring water was discovered within the rock after a large earthquake exposed a karstic spring residing within the Athenian Schist. A community well, known as the “Spring of Clepsydra,” was constructed in order to aid in the sustentation of Greek life .
When I first walked through the Propylaia, one of the first things I noticed was the sunlight coming through the marble pillars and celling beams (Fig. 4 & 5). I have long-since been fascinated by various ancient civilizations’ heightened sense of cosmic awareness. In a time when even moderate exposure to elements could dictate life or death, I realized, these structures were most likely constructed with the sunlight in the forefront of their plans.
As mentioned above, the Athenian Acropolis was constructed in the 13th century BC and it is suggested that it was not utilized as a worship site until the 6th century BC. With this in mind, I propose that the structures of the Acropolis were positioned strategically to protect Athenians from prolonged exposure to sunlight, harsh winds, rain and floods .
After observing a sustainable city, such as that of the Athenian Acropolis, other ancient sites also began to reveal their sustainable nature.
On the 4th day of our trip, we visited Ancient Thera (Fig. 6), a civilization inhabited by Dorian settlers from Sparta during the 9th century BC. The site lies within the saddle of two taller peaks, Mesa Vouno and Mt. Profitis Ilias on the southeastern end of Santorini’s crescent (Fig. 7). The massive layers of exposed sedimentary rock serve as a windshield as well as a vantage point. The coastal flat land that surrounds Ancient Thera, about 370 m below the saddle also heavily contributed to the Spartan’s survival by providing them with fertile terrain for agriculture.
Visiting both the Acropolis and Ancient Thera opened my eyes to the role geology can play in modern sustainability. We can utilize local resources and geography in order to benefit our own communities rather than importing goods and destroying land at unnaturally rapid rates.
 24 Feb 2012, Marble: Characteristics, Uses And Problems; http://www.gsa.gov/portal/content/111858 (accessed June 2015).
 Regueiro, M., Stamatakis M., Laskaridis K., The Geology of the Acropolis (Athens and Greece) European Geologist, November 2014.