This municipality has the coveted title "Cleanest Town in Cagayan." Located at the northernmost part of Cagayan, near Babuyan Channel. One of its 42 barangays, Fuga, is one dot of an island on the Babuyanes. The 42 barangays are distributed on its 26,460 hectare area, most of which are across the temperamental Cagayan River.

On May 11, 1680, Aparri town was officially inaugurated and was granted ecclesiastical recognition having for patron saint, Peter Thelmo. It is the only town which celebrates its town fiesta for 10 to 15 days with daily activities and nightly dancing, a showcase of the fun loving and frivolous traits of the Ibanags.

It is believed that Aparri got its name when the civil and religious authorities in Nueva Segovia (now Lallo) decided in 1604, to erect a church there for the evangelization of the natives. The many priest who celebrated the first mass there remained to supervise the construction of the church and continue their evangelization work subsequently, the natives referred to their place as "Aparrian," an Ybanag word meaning "where priests resided."

Noting the fast growth of "Aparrian" in population and its strategic location for a sea port, the Spanish Authorities in Nueva Segovia again decided on May 11, 1682 to separate the delta from Camalaniugan and Buguey and granted it ecclesiastical recognition and at the same time to elevate the community to the status of a "pueblo" or a township, hence, the word "aparte de Camalaniugan y Buguey." It was not long afterward, the word "aparte" was corrupted into "aparri" by the natives.

Before the coming of the settlers from the Ilocos Region, Aparri has already a port and galleons were coming from Acapulco, Mexico. Mexican goods were unloaded in Aparri in exchange for native commodities like lumber, tobacco, dried/fresh fish, rice, corn and many others.

By the 17th century, the ecclesiastical head in Nueva Segovia (the former capital of the province now called Lallo) lavished Aparri with Papal gifts, an ornate church, considered to be the best in Cagayan, was built. An earthquake, however, destroyed it.

During the last World War, the town proper of Aparri was a devastated by bombing done by the liberating Americans who wanted to rid the town of any Japanese squatter.