This 42m (138-ft.) slab of granite partially cut from the rock of an ancient quarry was probably destined to become the biggest column in Karnak. Masons discovered a flaw in the stone, however, and the project was abandoned, leaving the obelisk-to-be still attached on one side. Maybe the most impressive aspect of it is that its makers were fully prepared to cut loose this massive rock (it would have weighed in at more 1,100 tons), drag it down to the water, and barge it several hundred kilometers down the river with nothing more than some levers, ropes, and a whole lot of manpower.