Set on the banks of the Macal River with an area of 2061 square miles is the fast growing Cayo District. This district has a population of 40,000, the majority of which are Spanish speaking Mestizos and Maya Indians and a variety of Creoles,Garifunas, East Indians, Chinese, Lebanese and Mennonites. One fourth of the district's population resides in Belmopan, Santa Elena and San Ignacio, while the rest live in small villages or on farms.

Although the Cayo District lacks coral reefs and has no seashore, tourism is one of the most important industries in the district. Cayo is home to the largest Maya site of Caracol, and the most photographed ruin of Xunantunich; as well as offering the best in canoeing, river rafting, hiking, horseback riding and mountain biking in Belize.

Cayo is the Spanish word for island, and is believed to have been named by the early settlers when the area was bounded by two rivers. The only access to Cayo at that time was by boat, which took ten days to Belize City, or on horseback which took more than two weeks to a month.

The earliest settlers in this area were the Maya Indians, who put up the longest resistance against the Spaniards in the Americas. Many attempts were made by the Spaniards to control and convert the Indians but all were futile. The Spaniards weren't able to subdue the Indians until they had fallen victim to the European disease of smallpox. The disease had killed nearly the entire population. By the early 1700's the Spaniards were able to control and resettle the surviving Mayans in Guatemala.

The British and Creole loggers then set up camps in clearings where the Mopan and Macal River meet. This started the mahogany and chicle industry , San Ignacio being the major loading point on the Macal River. Eventually the mahogany was over harvested and chicle was replaced by synthetic rubber.

The economy of the district then eventually shifted to agriculture and cattle ranching. The first cattle ranch ever established in Belize was in the Cayo District by an American in 1950 . Today farmers are involved in raising cattle and pigs, growing sorghum,beans, fruit and various vegetables.