Within certain northern Atlanta neighborhoods there exists "walled" sanctuaries that are mostly invisible to those not of the Orthodox Jewish faith. It's called an eruv, and it's a fascinating example of how ancient culture can adjust to modern surroundings while flying largely under the radar.
Jewish custom forbids certain public "carrying" actions on Shabbat, or the Jewish Sabbath. For example, carrying keys, a tissue, food, or children outside the home on Shabbat is off-limits to Orthodox Jews. The concept of strictly distinguished public and private space is blurred with the evru, so it's not surprising that the word means "to combine" in Hebrew. Rules against public carrying are relaxed within the evru, fostering a sense of community among Orthodox Jews and making life more simple on Shabbat.
The physical makeup of an evru is relatively simple. With the permission of the appropriate landowners, a huge symbolic courtyard is created using horizontal and vertical members. In the case of the Atlanta area eruvim, telephone poles or tress form the vertical component, and strung wire serves as the "lintel." The real estate covered is usually a few square miles, and the evru includes at least one congregation within its confines.
A designated person is responsible for checking the condition of the evru on a weekly basis, because if the system of wires is broken, the evru becomes void of its relaxed rules. The first eruv in Atlanta went up in 1992 in Dekalb County's Toco Hills area. There are also eruvim in Dunwoody, Sandy Springs, Alpharetta/Johns Creek, and Virginia Highland. Click the links to see their specific boundaries.