Long time ago, the place was an important and busy trading port. Naturally, disagreements would arose and the combatants would run after each other. Sometimes robbers and other hoodlums fleeing the residents who pursued them usually got caught at this point.
This was so because they could go no farther unless they can cross by boats or rafts. Then people began calling the place, Lag-asan, from the local dialect meaning, a place where people ran after another.