| Castanhal | |
| Official Name: | Municipality of Castanhal |
| Settlement Type: | Municipality |
| Flag Size: | 100px |
| Seal Size: | 80px |
| Mapsize: | 250px |
| Pushpin Map: | Brazil |
| Pushpin Label Position: | bottom |
| Pushpin Map Caption: | Location in Brazil |
| Subdivision Type: | Country |
| Subdivision Name: |  Brazil |
| Subdivision Name1: | Northern |
| Subdivision Type2: | State |
| Subdivision Name2: | Pará |
| Subdivision Type3: | Demonym |
| Subdivision Name3: | castanhalense |
| Leader Title: | Mayor |
| Leader Name: | Paulo Titan |
| Established Title: | Founded |
| Established Date: | August 15, 1899 |
| Established Title1: | City Established |
| Established Date1: | January 28, 1932 |
| Area Total Km2: | 1,029.91 |
| Population As Of: | 2020 [1] |
| Population Total: | 203,251 |
| Population Density Km2: | auto |
| Timezone: | BRT |
| Utc Offset: | -3 |
| Coordinates: | -1.2969°N -47.9219°W |
| Elevation M: | 141 |
Castanhal is a city near the eastern edge of the state of Pará, Northern Brazil. It is located some 65 km east of the state's capital Belém and 50 km inland SE of the Bay of Marajo. It is accessed by car or bus via federal highway BR-316 . The climate is tropical rainforest. With a population around 200,000, it is the fifth largest city in the state.
coordinates: 1° 18′ S, 47° 55′ W
Castanhal was officially founded on January, 28th of 1932 (date of certification) and received its name due to the common nut trees (portug: Castanha) around the train station of the Bragança - Belém railway. Workers from the Brazilian Northeast started settling around the station. Local farmers started selling their products at the new market. Though, the new marketplace Castanhal was founded. The Bragança railway was shut down in 1964 and the rails were removed. The government of the state of Pará gave Castanhal the nickname "cidade modelo" (Model Town).In 2004, Pope John Paul II erected the diocese of Castanhal, which is subordinated as a suffragan diocese to the archdiocese of Belém, Pará.
Castanhal has become a regional center for education in the state of Pará. The educational level is well above the national average. There are eight secondary schools and three universities:
Due to its convenient geographic location, Castanhal has become an important trading spot for food and agricultural products (cereals, corn, maniok, pepper, palm oil), affecting the entire Northeastern part of the state and beyond.
Likewise Castanhal is becoming a hot spot for technology.
There are energy companies, specialized in high-voltage and high tech well drilling. Further, there is a factory producing work boots for food industry as well as an industry producing metallurgical equipment for mining companies.[5]