The Devil, he did!
You might think that the Romans built the aqueduct in Segovia.
The locals beg to differ. It was Old Harry.
According to a local legend, a 16 year old girl, fed up with walking the 16km (10 miles) to the nearest spring for water every day, said she'd sell her soul to the Devil if there was water in the town.
Harry heard, and agreed that if it could be done in one night, her soul would be his.
Harry and his imps got to work at sunset.
The girl started praying to the Madonna.
And the race was on.
Long story short, the Madonna took pity on the girl and made the sun rise before it should have.
The Devil lost, the girl won and Segovia has an aqueduct.

At least Harry was tempted to do something constructive.
In Chesterfield, UK, locals say he was so enraged by the town's piety(!) he wrapped his tail round the spire of the local church and tried to pull it off.
Being constructed by good Derbyshire builders, the spire twisted, but stayed attached.
