The first, called Caraballo del Sur, forms the nucleus of the system and has its highest peaks in the border between the provinces of Abra, Ilocos Norte and Cagayan.

In early 1898, the provinces of Zambales, Ilocos, Pampanga, Bulacan, Laguna, Pangasinan, Nueva Ecija, Tarlac.

Mountain Province is bounded in the east by Isabela, in the north by the provinces of Kalinga, Apayao, and Abra, in the south of Benguet and Ifugao, and in the west by the province of Ilocos Sur.

The region is composed of four provinces, namely: Ilocos Norte, Ilocos Sur, La Union and Pangasinan.

These resentments bubbled to the surface at various points in the Ilocos provinces ' history as insurrections, most notably that of Andres Malong and Palaris of Pangasinan, Diego Silang and his wife Gabriela Silang in 1764, and the Basi Revolt in the 19th century.

Ilocos collectively refers to two provinces in the Philippines: Ilocos Norte and Ilocos Sur.

The Ilocos Region, containing four provinces, is named after Ilocos.

Although their homeland constitutes the provinces of Ilocos Norte, Ilocos Sur, La Union and Abra, their population has spread east and south of their original territorial borders.

As a reward for his services to the King of Spain, Salcedo was awarded the old province of Ilocos which consisted of the modern provinces of Ilocos Norte, Ilocos Sur, Abra, La Union and part of Mountain Province as his hacienda ( estate ), and was accorded the title of " Justicia Mayor de esta Provincia de Ylocos " ( Province Mayor of Ilocos ).

Some Chinese-Filipinos joined the soldiers were integrated of the 11th, 14th, 15th, 66th & 121st Infantry Regiment of the U. S. Armed Forces in the Philippines-Northern Luzon ( USAFIP-NL ) under the military unit of the Philippine Commonwealth Army started the Liberation in Northern Luzon and aided the provinces of Ilocos Norte, Ilocos Sur, La Union, Abra, Mountain Province, Cagayan, Isabela and Nueva Vizcaya and attacking Imperial Japanese forces.

As of 2008, leaders from the Ilocos region and other Ilocano-dominated provinces are considering the possible declaration of Ilocano language as an official language in their provinces along with the national language to foster the continuity of their language and heritage.

Going north, it is a two-hour ride to Pangasinan, a three-hour ride to Baguio City, the Summer Capital of the Philippines, and around six-hour ride to the Ilocos provinces.

When news of Aguinaldo's arrival there reached the towns of central Luzon, men from the Ilocos provinces, Nueva Ecija, Pangasinan, Tarlac, and Zambales renewed their armed resistance against the Spanish.

Cane vinegar, made from sugarcane juice, is most popular in the Philippines, in particular, the Ilocos Region of the northern Philippines ( where it is called sukang iloko ), although it also is produced in France and the United States.

Ilocos Norte ( Ilokano: Amianan nga Ilocos ; Filipino: Hilagang Ilokos ) is a province of the Philippines located in the Ilocos Region in Luzon.

* St. Monica Parish Church in Sarrat-documented to be the biggest church in the Ilocos Region.

Ilocos Sur ( Ilokano: Abagatan nga Ilokos, Filipino: Timog Ilokos ) is a province of the Philippines located in the Ilocos Region in Luzon.

La Union is a province of the Philippines located in the Ilocos Region or Region 1 in Luzon, whose capital is San Fernando City and borders Ilocos Sur to the north, Benguet to the east, and Pangasinan to the south.

Most of the members of the Church are from the northern part of Luzon, especially in the Ilocos Region.

Most members of the Church are from the northern part Luzon, especially in the Ilocos Region where Obispo Máximo Aglipay was born.

The Ilocos region or Region I ( Ilokano: Rehion ti Ilocos, or Deppaar ti Ilocos ; Pangasinan: Rihiyon na Sagor na Baybay na Luzon ( Region at the Northwest Coast of Luzon )) is a Region of the Philippines and is located in the northwest of Luzon.

The use of the term Ilocos Region promotes the wrong notion that all the residents of Region 1 are Ilocanos.

Cruz, which is known as Digos that time, lured many migrants, majority of whom came from the Visayas and Ilocos regions to settle permanently in the area.

Its capital is Laoag City and is located at the northwest corner of Luzon Island, bordering Cagayan and Apayao to the east, and Abra and Ilocos Sur to the south.

Ilocos Norte is noted for being the birthplace of former President Ferdinand E. Marcos, who led an authoritarian rule over the country during the latter half of his incumbency.

Ilocos Norte is also known as a northern tourist destination, being the location of Fort Ilocandia, an upper class hotel and beach resort famous among expatriates, and Pagudpud.

Ilocos Norte is home to several famous Roman Catholic churches:

Ilocos Norte is the home of the Aglipay Shrine ( Aglipayan Church ) where the church's first supreme leader was buried.

There is currently a 25 Megawatt wind farm in Ilocos Norte, and several more wind energy projects are being planned

Political map of Ilocos NorteIlocos Norte is subdivided into 558 barangays, 21 municipalities, and 2 cities.

Ilocos Sur is bordered by Ilocos Norte and Abra to the north, Mountain Province to the east, La Union and Benguet to the south, and the South China Sea to the west.

Ilocos Sur is subdivided into 32 municipalities and 2 cities.

Ilocos Sur is located along the western coast of Northern Luzon.

It is bordered by Ilocos Norte to the north, Abra to the northeast, Mountain Province to the east, Benguet to the southeast, La Union to the south, and the China Sea to the west.

The topography of Ilocos Sur is undulating to rolling with elevations ranging from 10 to 1, 700 meters above sea level.

The earliest historical account of the Municipality was recorded in 1572 when Captain Juan de Salcedo, a Spanish conquistador colonized the region of Ilocos Sur and founded Vigan as capital.

A report in 1902 describes Santa Maria as pueblo along the coast of Ilocos Sur, Luzon, ( with ) several cart roads that led to the interior ; a city that built and by way of historical note, adds that on December 3, 1900, 2, 150 insurrectos surrendered here, ( and ) took oath of allegiance to the United States.

A report published in 1902, but which includes observations made earlier has this to say of Santa Maria: " a pueblo on coast highway in Ilocos Sur, Luzon ; several cart roads lead to interior ; a city, well built and, by way, of a historical footnote, adds that on " December 3, 1900.

It was established by five pioneering Ilocanos whose vision was to provide quality computer education to the youth of Ilocos Sur.

Camiling's one town one product the famous Chicharon or Bagnet by the Ilocanos of Ilocos Sur and the sweet green native cakes called Iniruban or Dirimin.

Several years before the Philippine Revolution, the Ilocanos from Tarlac, Pangasinan, Ilocos Region and some parts of Nueva Ecija, especially the towns of Sto.

Ilocanos, believed to have been of Malay origin, along with the Isnegs and the Tinguians, who eventually populated the hinterlands of Ilocos, were the early inhabitants.

The complete subjection of the whole Ilocos region was a long, painful process, however, as most Ilocanos did not readily accept the Spanish conquerors.

Due to the influx of migration from Ilocos, Ilocanos settled in outlying areas.

Ilocanos mainly from Ilocos Sur, among them future town mayor Santos Martinez, discovered it in quest for better land and eventually dominated the area.

The vast virgin forest and fertile soil of the place was pioneered by enterprising Ilocanos from the Ilocos Province, particularly from Ilocos Norte and some Yogads who are natives of Cagayan Valley.

Much of the population is Ilocanos, descendants of migrants from Ilocos.