Northward of Nippur was Bab-ili or Babylon, "the Gate of God," a Semitic translation of its original Sumerian name, Ka-Dimirra. It was a double city, built on either side of the Euphrates, and adjoining its suburb of Borsippa, once an independent town. Babylon seems to have been a colony of Eridu, and its god, Bel-Merodach, called by the Sumerians "Asari who does good to man," was held to be the son of Ea, the culture-god of Eridu. E-Saggil, the great temple of Bel-Merodach, rose in the midst of Babylon; the temple of Nebo, his "prophet" and interpreter, rose hard by in Borsippa. Its ruins are now known as the Birs-i-Nimrûd, in which travellers have seen the Tower of Babel. In the neighbourhood of Babylon were Kish (_El-Hymar_) and Kutha (_Tel-Ibrahim_); somewhat to the north of it, and on the banks of the Euphrates, was Sippara or Sepharvaim, whose temple, dedicated to the Sun-god, has been found in the mounds of Abu-Habba. Sippara was the northern fortress of the Babylonian plain; it stood where the Tigris and Euphrates approached most nearly one another, and where, therefore, the plain itself came practically to an end. Upi or Opis, on the Tigris, still farther to the north, lay outside the boundaries of primæval Chaldæa. East of Babylonia were the mountains of Elam, inhabited by non-Semitic tribes. Among them were the Kassi or Kossæeans, who maintained a rude independence in their mountain fastnesses, and who, at one time, overran Babylonia and founded a dynasty there which lasted for several centuries. The capital of Elam was Susa or Shushan, the seat of an early monarchy, whose civilisation was derived from the Babylonians. In the south the Tigris and Euphrates made their way to the region of salt-marshes, called Marratu in the inscriptions, Merathaim by the prophet Jeremiah. They were inhabited by the Semitic tribe of the Kaldâ, whose princes owned an unwilling obedience to the Babylonian kings. One of them, Merodach-baladan, succeeded in making himself master of Babylonia, and from that time forward the Kaldâ became so integral a part of the population as eventually to give their name to the whole of it. For the writers of Greece and Rome the Babylonians are Chaldæans. It is probable that Nebuchadrezzar was of Kaldâ origin; if so, this would have been a further reason for the extension of the tribal name to the whole country.