Cauayan, officially the City of Cauayan, is a 2nd class component city in the province of Isabela, Philippines. According to the 2020 census, it …Cauayan, officially the City of Cauayan, is a 2nd class component city in the province of Isabela, Philippines. According to the 2020 census, it has a population of 143,403 people. Cauayan derives its name from the word Cawayan meaning bamboo or bulo in the Ilocano language, which was spoken by the early settlers of the area. Local aural history suggests that early Spaniards reached the place and found abundant bamboo trees along creeks that circled the town sites of Bulod, Sipat, Bungkol, and Marabulig creeks where a few families lived - and so that became the name of the area. It was also a common to see crocodiles basking under the cluster of bamboo along the creeks in the early morning sun.