Final answer:
The Walls of Babylon, the Ishtar Gate, and the Hanging Gardens were built by Nebuchadnezzar II during the Neo-Babylonian Empire and were major achievements of the Babylonian Empire.
Step-by-step explanation:
The Walls of Babylon, the Ishtar Gate, and the Hanging Gardens have in common that they were built by Nebuchadnezzar II during the Neo-Babylonian Empire. These structures were major accomplishments of the Babylonian Empire. The Walls of Babylon were a defensive fortification surrounding the city, the Ishtar Gate was a grand entrance to the city adorned with impressive glazed brickwork, and the Hanging Gardens were a remarkable feat of engineering and horticulture, considered one of the Seven Wonders of the Ancient World.
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