Downspouts are usually vertical and usually extend down to ground level. The water is directed away from the building's foundation, to protect the foundations from water damage. The water is usually piped to a sewer, or let into the ground through seepage.
The first even downspout to be installed was in 1240 on the Tower of London, as it was whitewashed and the newly painted walls had to be protected from the rain. Decorative heads are sometimes added, these being low-height gargoyles.
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