Alexandria is the second-largest city in Egypt and its largest seaport. Alexandria extends about 20 miles (32 km) along the coast of the Mediterranean Sea in north-central Egypt. It is home to the Bibliotheca Alexandrina, the New Library of Alexandria, and is an important industrial center because of its natural gas and oil pipelines from Suez.
In ancient times, the city was known for the Lighthouse of Alexandria (one of the Seven Wonders of the Ancient World) and the Library of Alexandria (the largest library in the ancient world). Ongoing maritime archaeology in the harbour of Alexandria (which began in 1994) is revealing details of Alexandria both before the arrival of Alexander, when a city named Rhakotis existed there, and during the Ptolemaic dynasty.
The city of Alexandria was named after its founder, Alexander the Great, and as the seat of the Ptolemaic rulers of Egypt, quickly became one of the greatest cities of the Hellenistic world — second only to Rome in size and wealth. However, upon the founding of Cairo by Egypt's medieval Islamic rulers, its status as the country's capital ended, and fell into a long decline, which by the late Ottoman period, had seen it reduced to little more than a small fishing village. The current city is Egypt's leading port, a commercial and transportation center, and the heart of a major industrial area where refined petroleum, asphalt, cotton textiles, processed food, paper, plastics, and styrofoam are produced.
Very little of the ancient city has survived into the present day. Much of the royal and civic quarters sank beneath the harbor due to earthquake subsidence, and much of the rest has been rebuilt upon in modern times.
"Pompey's Pillar" is the most well-known ancient monument still standing. It is located on Alexandria's ancient acropolis — a modest hill located adjacent to the city's Arab cemetery — and was originally part of a temple colonnade. Including its pedestal it is 30 m (99 feet) high; the shaft is of polished red granite, roughly three meters in diameter at the base, tapering to two and a half meters at the top. The structure was plundered and demolished in the 4th century when a bishop decreed that Paganism must be eradicated. "Pompey's Pillar" is a misnomer, as it has nothing to do with Pompey, having been erected in 293 for Diocletian, possibly in occasion of the rebellion of Domitius Domitianus. Beneath the acropolis itself are the subterranean remains of the Serapeum, where the mysteries of the god Serapis were enacted, and whose carved wall niches are believed to have provided overflow storage space for the ancient library.
Alexandria's catacombs, known as Kom al Sukkfa, are a short distance southwest of the pillar, consist of a multi-level labyrinth, reached via a large spiral staircase, and featuring dozens of chambers adorned with sculpted pillars, statues, and other syncretic Romano-Egyptian religious symbols, burial niches and sarcophagi, as well as a large Roman-style banquet room, where memorial meals were conducted by relatives of the deceased. The catacombs were long forgotten by the citizens until they were discovered by accident in the 1800s.
The most extensive ancient excavation currently being conducted in Alexandria is known as Kom al Dikka, and it has revealed the ancient city's well-preserved theatre, and the remains of its Roman-era baths.
Information based on http://en.wikipedia.org/wiki/Alexandria