Jonah 3:3 - Wesley's Explanatory Notes

Exceeding great — The greatest city of the known world at that day, it was then in its flourishing state greater than Babylon, whose compass was three hundred eighty — five furlongs, but Nineveh was in compass, four hundred and eighty. It is said, her walls were an hundred foot in height, her walls broad enough for three coaches to meet, and safely pass by each other; that it had fifteen hundred towers on its walls, each two hundred foot high, and one million, four hundred thousand men employed for eight years to build it. Of three days journey — To walk round the walls, allowing twenty miles to each day's journey.