Ravan, the king of Lanka and the main antagonist of the Hindu epic Ramayana was an ardent devotee of Shiva. Sometime before the main events of Ramayana unfolded, Ravan prayed to Shiva and got hold of a powerful relic - Atma Lingam. (demons praying to gods and getting powerful relics / boons is a recurring theme in Hindu mythology). Shiva though, places a condition, that Ravan has to carry the Atma Lingam, without putting it down on the ground, until he reaches home - Lanka.
The rest of the gods worry that Ravan would become immensely powerful and hard to defeat. The gods hatch a plan to ensure that Ravan puts the AtmaLingam on the ground before reaching Lanka. Ganesh Shiva’s son - agrees to carry out the scheme.
As Ravan is passing by Gokarna, in modern day Karnataka, India - the gods hide the sun. Ravan believing that it is dusk, wants to prey as is his routine. Precisely at that point he is approached by Ganesh, disguised as a priest. Ravan asks the priest to hold the AtmaLingam while he prays for a bit. Ganesh, agrees albeit with a condition that he will call his name three times, if Ravan does not respond, he will place the AtmaLingam on the ground. Ravan agrees and proceeds to pray. Ganesh places the AtmaLingam on the ground, without calling out thrice. He basically cheats.
The relic now on the ground cannot be moved. Ravan is devastated and tries to lift the AtmaLingam, but it won’t budge. His force breaks a piece of the head of the Lingam. This piece falls a few hundred kilometers southwards. The place where the stone falls is called Sirathkal (meaning head stone) in the local Tulu language. Ravan obviously goes back home dejected.
In modern times Sirathkal is known as Surathkal, a suburb of Mangalore. I spent four years studying Computer Engineering there at NITK Surathkal.
I am curious about how places get their names, this was the story of Surathkal.