Trade with neighboring towns along the southern coast of Puerto Rico and Saint Thomas was conducted through the port of Maunabo which was built in 1812.

One early institution the Church of San Isidro Labrador y Santa Maria de la Cabeza was established in 1799.

The leading landowners exercised political influence as mayors and counselors but the pace of economic development remained slow.

By 1869 the slave register for compensation of the slaveowners at the time of abolition documented over 250 names of enslaved Afro-Puerto Ricans in Maunabo.

The factory site was 6.2 acres and located alongside the Maunabo River on land ceded to the new company by the Hacienda Garonne.

Thereafter the Columbia was a medium sized factory that served as an economic focal point for Maunabo but its growth was constrained by geography.

Small and medium sized colonos were responsible for transporting clean sugars to the factory and paid a 5% charge for processing.

After the sale of the factory and related lands to the Puerto Rican government in 1936, the site continued to be used as a way station for Maunabo sugar producers until 1974.

Puerto Rico was ceded by Spain in the aftermath of the Spanish–American War under the terms of the Treaty of Paris of 1898 and became a territory of the United States.

In 1899, the United States Department of War conducted a census of Puerto Rico finding that the population of Maunabo was 6,221.

Being almost "disconnected" from the rest of the island by its high mountains, the maunabeños created their own newspaper called La Esquina[10] ("The Corner" in English) on August 30, 1975 by Ramón "Chito" Arroyo and José Orlando Rivera.

It started as a community one-sheeter distributed free of charge only in Maunabo, but its popularity was so overwhelming that a year later it was transformed into a monthly tabloid.

Today, the paper still is free of charge, home delivering 40,000 copies not only in Maunabo but also in the southeastern towns of Guayama, Arroyo, Patillas, Yabucoa and Humacao, and read by more than 190,000 people.

At Sierra Guardarraya the strong winds have affected the growth of vegetation and the tall grass only grows flat to the ground.

In the lush and tropical vegetation of Cerro de la Pandura you will find one of the Island's most endangered species of coquí.

The municipal buildings, central square and large Catholic church are located in a barrio referred to as "el pueblo".

[34] With an almost unspoiled culture—due to the high mountains that separate the town from the rest—Maunabo still is a bucolic city and the lack of large commercial chains gives it a unique personality compared to the rest of the island.

[35][36] The town is also known for its Punta Tuna Lighthouse[37] built by the Spanish at the end of the 19th century before the Island was turned over to the United States as spoils of the Spanish–American War of 1898.

Due to Law 180[38] presented by Governor Aníbal Acevedo Vilá, the doors of the lighthouse were opened once again to the public in February 2006.

[39] The town is also known for its annual crab carnival "Festi-Carnaval Jueyero" which attracts thousands of visitors for a three-day celebration with live music, street fairs, contests and much crab-based food.