Both of the quotes are not really appropriate. The most striking dimension of the
Chinese Wall is not its strength, but its length, which makes it possible for
astronauts orbiting over it to identify it. An interesting detail about it is that
much of it is constructed of compacted laterite soil, which is very resistant
to weathering.

I often wondered why the Great Wall was a significant obstacle. If you look
at pictures of it, it would not be hard to climb. It just occurred to me that
it would be very hard for an invader to get his horses over it.