i dont see why an 800 foot tall coaster isnt possible, thats less than 2x the height of dragster! i think that 800 feet is completely in range
and speaking of a 1000 foot ride, they could put it on the side of the stratosphere tower! the top of that thing is already an amusement park! it would be awsome! a 1000 foot drop! thats like...200 mph! hehe (i think the natural speed limit for humans in freefall while skydiving is 340 mph, i dont know for coasters
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