If you visit Budapest, one of the most spectacular tourist destinations you will probably be directed to is the Gellérthegy (Gellért's Hill). It is a steep, rocky hill right by the Danube, and a great vantage point.
Back in the day, it was also a prime site for making instant saints out of people.
Once again, we are back to István I. During his reign, a priest from Venice called Gerardo Sagredo was brought to him by some over-eager Hungarian abbot - Gerardo was on his merry way to live in the Holy Land, but the Hungarians convinced him to bring his talents in conversion to the new Hungarian kingdom instead. Gerardo - known to us as Gellért - ended up as the personal mentor to István's devout young son Prince Imre (remember him?), and stayed in Hungary for the rest of his life.
After István's death, Gellért was fairly active not only in conversions, but also in politics. He did not support either of the following kings - Pietro Orseolo from his hometown, or Aba Sámuel from one of the Hungarian families - but he did like the idea of Vazul's sons returning home from exile. According to his legend, he was on his way to greet them in Buda in 1046 when he was captured.
In order to make the execution spectacular, they put Gellért in a two-wheeled cart and rolled him down the side of the hill. If you look at some pictures, you know that had to be bad to begin with, and yet according to some sources Gellért was still alive when he reached the bottom. In order to make sure he was dead they stabbed him with a spear, and then broke his head on a rock.
Gellért was sainted together with István I and Prince Imre a mere 37 years later. He is buried in Venice. They named the hill after him in reverence, and ever since then we all learn the story of how it got that name.