Caloocan is divided into two geographical locations with a total combined area of 5,333.40 hectares (13,179.1 acres), a result of the 1949 expansion of Quezon City, which absorbed much of its territory.

It is composed of mostly residential subdivisions and extensive resettlement areas with scattered distribution of industrial estates mostly within road transit points and intersections.

Variation, and the apparent confusion over the spelling, came about during the early 1970s, when a resolution was adopted by the municipal board, requiring the city departments to use the name "Kalookan."

[8][9] Although confusion persists, the general inclination in the city is towards "Caloocan," as evidenced by the official logo and favored by many barangays, schools, and newspapers.

"[10][11] Originally, Caloocan was the area where the old town of Tondo and Tambobong met, located along the shores of Dagat-Dagatan, a crescent-shaped inland lagoon to the west.

The settlement along the shore was called "Aromahan", or "Espina" to the Spaniards, and was separated from Manila Bay by a narrow ridge from Tondo towards an opening in Kinabutasan leading to the sea.

To escape the Spanish authorities, many from the area abandoned the town proper and sought refuge in the grasslands of Balintawak and Pugad-Lawin, in which the people fought the landlords of Hacienda de Maysilo for terrestrial rights, which went on for almost a hundred years.

In a house in Caloocan, secret meetings were held by Andrés Bonifacio and his men, and it was in the city's perimeters where the first armed encounter took place between the Katipunan and the Spaniards.

The men of Caloocan fought the new invaders on February 23, 1899, however victory eluded the local troops on the pretext of Antonio Luna's rift with Emilio Aguinaldo's loyalists.

[7] Caloocan remained a city of the province of Rizal until November 7, 1975, when it became a part of the National Capital Region or Metro Manila, by virtue of Presidential Decree No.

502 created Quezon City in 1939, Caloocan ceded 1,500 hectares of land from the barrios or sitios of Bagubantay (Bago Bantay), Balintauac (Balintawák), Balingasa, Kaingin, Kangkong (present-day Apolonio Samson), La Loma, Malamig, Matalahib (present-day Santo Domingo), Masambong, Galas, San Isidro, San José, Santol and Tatalon.

[26][27] A bill authored by city's 1st district representative Virgilio Robles,[26] which aimed to reduce the barangays from 188 to 60—thirty in each legislative district—was approved as Republic Act (RA) No.

[35][36][37][38] However, the Peace Research Institute Frankfurt (PRIF) noted in 2020 that Malapitan's mayorship was characterized with a passivity towards President Rodrigo Duterte's war on drugs during its first year (2016–2017), with Malapitan asking the local branch of the Philippine National Police (PNP) to take charge of crime control and work vigorously against illegal drugs,[39][40] which PRIF claimed to have "resulted in a huge spike of deadly police violence" and "excessive levels of vigilantism" during this period.

702, sponsored by councilors Mercado, Onet Henson and Alou Nubla, in early September that implemented a new curfew for minors (from 10 p.m. to 5 a.m.) and placed the liability on their parents in response to the police murders of delos Santos, Arnaiz and de Guzman.

[7] South Caloocan, where most commercial and industrial establishments are found, lies on generally flat and highly accessible land, with slopes ranging from 0–3%.

[55] North Caloocan is characterized by gently to steeply undulating to rolling topography with slopes ranging from 3–18%, mostly seen in the northern and central portion, gradually transforming into a southward trend of flat lands down to the southwestern tip of the boundary.

[55] Eastward of South Caloocan, large areas consisting of tuff and tuffaceous sediment can be traced, spreading towards the whole eastern side of Metro Manila.

On the northeast borders of North Caloocan, conglomerate rocks were traced, crossing Tala Estate and extending to the province of Bulacan and the La Mesa Watershed.

Others include the Bagong Silang River, Tala, Camarin, Pasong Malapad, and Bagumbong Creeks crossing multiple subdivisions, for 52.7 kilometers (32.7 mi) long within the city's territorial boundaries.

The MOU preempted any court decisions on the dispute that began in 2001, when Malabon, upon its conversion to a highly urbanized city, took control over lands formerly under Caloocan's jurisdiction.

If the two districts were treated as separate cities, they still would have been among the largest in the country as of the 2015 census year, ranking fourth and 17th respectively in terms of population.

The currently under construction MRT Line 7 has also two under-construction stations located at the northern part of Caloocan, namely: Sacred Heart and Tala.

The city has an extensive network of roads, the most prominent being Epifanio de los Santos Avenue, which begins in the Monumento area.

The North Luzon Expressway's Operations and Maintenance Center and the motorway's Balintawak toll barrier are in the southern part of Caloocan.

Bus line Victory Liner Incorporated has its headquarters and terminal along Rizal Avenue Extension near the Monumento station.

The city's most celebrated landmark is the monument to the revolutionary Andrés Bonifacio, which stands on a roundabout where EDSA, MacArthur Highway, Samson Road, and Rizal Avenue Extension intersect.

Recent renovations have been made on the environs of the monument, including the Bonifacio Circle, its former site, and the Caloocan stretch of EDSA, which is 100 meters (330 ft) away from the landmark.

Other sites of historical importance identified by the city government include a lot in P. Zamora Street where the wife of Katipunan leader Andrés Bonifacio once resided; the heritage house of Gertrudes Sevilla, the owner of which is the nephew of Gregoria de Jesús;[86][82] Santa Quiteria Church in Baesa; and Our Lady of Grace Parish in 11th Avenue; La Loma Cemetery, the oldest cemetery in Manila; and Thai To Taoist Temple along 6th Avenue.

However, the whole Caloocan city police force was recently sacked after a series of crimes, including killings and robberies, were committed by its members.

Private institutions such as the Philippine Cultural College (Annex), Saint Benedict School of Novaliches, the Diocese of Kalookan's St. Gabriel Academy, St. Mary's Academy of Caloocan City, Notre Dame of Manila, and Santa Elena School of Novaliches are also located in the city.