Despite being far from the city centre, Kartal is heavily populated (total population of 541,209) (2008 census). The total land area is 147,000 m² which includes some countryside areas inland. Her neighbours are Maltepe the west, Sultanbeyli and Sancaktepe the north and Pendik the east.
It was the neighbour of Gebze (1923–1987), Şile (1923–1987), Beykoz (1928–1987), Üsküdar (1923–1987), Ümraniye (1987–2009) and Kadıköy (1928–1992 and 2004–2009). It was a neighbour again with Kadıköy from the northwest due to Ferhatpaşa quarter passed from Maltepe to Samandıra in 2004. However, this neighbourhood was ended with Ataşehir's separation from Kadıköy and Samandıra's separation (joined to Sancaktepe) from Kartal in 2009.
The center of Kartal (meaning 'eagle' in Turkish) was a fishing village on the Marmara shore during the Byzantine Empire called Kartalimen or Kartalimin in Greek, and was founded at the beginning of the 6th century. In the 11th century, the town was conquered by the ruler of the Seljuks, Suleyman Shah, and then in 1329 Kartal became part of the Ottoman Empire (however, the Byzantines re-took the city in 1403 and held it for 17 years).
The current trend is that as more and more housing is built near the coast, factories there are being closed down and moved inland. For example, the large cement factory on the shore, which is to be converted into a cultural center, was closed in 2003.
There is an historical Roman bath ruin near the Dragos Hill, which was under use of late Roman era is recovering by the Istanbul Archaeology Museums with the financial support of Kartal Municipality.