Alajuela Province in the context of Sarchí Norte

Arenal Volcano (Spanish: Volcán Arenal) is a recently active andesitic stratovolcano in north-western Costa Rica around 90 km (56 mi) northwest of San José, in the province of Alajuela, canton of San Carlos, and district of La Fortuna. The Arenal volcano stands 1,633 metres (5,358 ft) high. It is conically shaped with a crater 140 metres (460 ft) in diameter. Geologically, Arenal is considered a young volcano and it is estimated to be less than 7,500 years old. It is also known as "Pan de Azúcar", "Canaste", "Volcan Costa Rica", "Volcan Río Frío" or "Guatusos Peak".

The volcano was dormant for hundreds of years and exhibited two craters at its summit, with minor fumaroles activity, covered by dense vegetation. In 1968 it erupted unexpectedly, destroying the small town of Tabacón. Due to the eruption three more craters were created on the western flanks but only one of them exists today. By duration, Arenal's eruption from 1968 to 2010 is the tenth longest volcanic eruption on Earth since 1750. Since 2010, Arenal has been dormant.

Puntarenas (Spanish pronunciation: [puntaˈɾenas]) is a province of Costa Rica. It is located in the western part of the country, covering most of Costa Rica's Pacific Ocean coast, and it is the largest province in Costa Rica. Clockwise from the northwest, it borders on the provinces Guanacaste, Alajuela, San José and Limón, and the neighbouring country of Panama.

San José (Spanish pronunciation: [saŋ xoˈse]) is a province of Costa Rica. It is located in the central part of the country, and borders (clockwise beginning in the north) the provinces of Alajuela, Heredia, Limón, Cartago and Puntarenas. The provincial and national capital is San José. The province covers an area of 4,965.9 km². and has a population of 1,404,242.

The Central Valley (Spanish: Valle Central) is a plateau and a geographic region of central Costa Rica. The land in the valley is a relative plain, despite being surrounded by several mountains and volcanoes, the latter part of the Central Range. The region houses almost three quarters of Costa Ricans, and includes the capital and most populous city, San José. The valley is shared among the provinces of Alajuela, Heredia, San José and Cartago. The region occupies an area of 11,366 km, more than a fifth of the country, and is drained by the Tárcoles River on the west side and by the Reventazón River on the east side.

Alajuela (Spanish pronunciation: [alaˈxwela]) is a district in the Alajuela canton of the Alajuela Province of Costa Rica. As the seat of the Municipality of Alajuela canton, it is awarded the status of city. By virtue of being the city of the first canton of the province, it is also the capital of the Province of Alajuela.

Because of its location in the Costa Rican Central Valley, Alajuela is nowadays part of the conurbation of the Greater Metropolitan Area. The city is the birthplace of Juan Santamaría, the national hero of Costa Rica and the figure who gives the name to the country's main international airport, which is south of Alajuela downtown.

Juan Santamaría International Airport (Spanish: Aeropuerto Internacional Juan Santamaría) (IATA: SJO, ICAO: MROC) is the primary international airport serving San José, the capital of Costa Rica. The airport is located in Alajuela Province, 20 kilometres (12 mi; 11 nmi) northwest of downtown San José. It is named after Costa Rica's national hero, Juan Santamaría, a drummer boy who died in 1856 defending his country against forces led by William Walker, an American filibuster. It is the biggest and busiest airport in Costa Rica and second in Central America, transiting more than 5 million passengers per year before COVID.

The airport is a hub for Avianca Costa Rica, Costa Rica Green Airways, Sansa Airlines, and Volaris Costa Rica, and a focus city for Avianca El Salvador and Copa Airlines. It was the country's only international gateway for many years, before the opening of the international airport in Liberia, Guanacaste. Both airports have direct flights to North and Central America and Europe, but Juan Santamaría International Airport also serves cities in South America and the Caribbean.

Guanacaste (Spanish pronunciation: [ɡwanaˈkaste]) is a province of Costa Rica in the northwestern part of the country, along the coast of the Pacific Ocean. It is bordered by Nicaragua to the north, Alajuela Province to the east, and Puntarenas Province to the southeast. It is the most sparsely populated province in Costa Rica. Guanacaste has an area of 10,141 square kilometres (3,915 sq mi) and as of 2010, had a population of 354,154, with annual revenue of $2 billion.

Guanacaste's capital is Liberia. Other important cities include Cañas and Nicoya.

San Carlos is a canton in the Alajuela province of Costa Rica, with an estimated population of 198,742 as of 2022. It ranks as the fourth-most populous canton in the country and is the 1st largest by area. It borders Nicaragua to the north, San Ramón, Zarcero and Sarchí the south, Río Cuarto and Sarapiquí to the east, and Los Chiles, Guatuso, Tilarán and San Ramón to the west. The capital city of the canton is Ciudad Quesada.

The canton is known for its extensive plains, high levels of rainfall, and fertile soils, which make it one of Costa Rica’s most productive economic regions. Its economy is driven by a wide range of agricultural activities, including cattle ranching, beef and dairy production, and the cultivation of crops such as sugarcane, pineapple, citrus fruits, tubers, and basic grains.

La Fortuna is a district of the San Carlos canton, in the Alajuela province of Costa Rica.