Matanzas River is a body of water located in St. Johns

St. Johns County, Florida

St. Johns County is a county located in northeastern Florida. As of the 2010 census, the population was 190,039. The county seat is St. Augustine. Due to the inclusion of Ponte Vedra Beach, it is one of the highest-income counties in the United States....

 and Flagler

Flagler County, Florida

Flagler County was created in 1917 from portions of Saint Johns and Volusia counties. It was named for Henry Morrison Flagler, a famous railroad builder who built the Florida East Coast Railway. Bunnell is the county seat of Flagler County....

 counties in Florida

Florida

Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...

. It is a narrow saltwater bar-bounded estuary

Estuary

An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....

 sheltered from the Atlantic Ocean

Atlantic Ocean

The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...

 by Anastasia Island

Anastasia Island

Anastasia Island is a barrier island which is approximately long located off the northeast Atlantic coast of Florida in the United States. The island is located east and southeast of St. Augustine. It is separated from the mainland by the Matanzas River, part of the Intracoastal waterway, Matanzas...

.

The Matanzas River is 23 miles (37 km) in length and extends from St. Augustine

St. Augustine, Florida

St. Augustine is a city in the northeast section of Florida and the county seat of St. Johns County, Florida, United States. Founded in 1565 by Spanish explorer and admiral Pedro Menéndez de Avilés, it is the oldest continuously occupied European-established city and port in the continental United...

 Inlet southward to approximately 6.5 miles (10.5 km) south of the Matanzas Inlet

Matanzas Inlet

Matanzas Inlet is a channel in Florida between barrier islands connecting the Atlantic Ocean and the south end of the Matanzas River. It is south of St. Augustine, in the southern part of St. Johns County, at coordinates...

 on the southern tip of Anastasia Island. The river is part of the Intracoastal Waterway

Intracoastal Waterway

The Intracoastal Waterway is a 3,000-mile waterway along the Atlantic and Gulf coasts of the United States. Some lengths consist of natural inlets, salt-water rivers, bays, and sounds; others are artificial canals...

.

The Matanzas River at St. Augustine was the main entrance to the historic city, America's oldest port. The body of water is often referred to as the Matanzas Harbor in the immediate vicinity of the city's waterfront. The southern portion of the Matanzas River was traditionally considered the "backdoor" to the city of St. Augustine, and control of the river was considered a strategic necessity for early Spanish colony at St. Augustine. Spanish engineers and laborers built Fort Matanzas

Fort Matanzas National Monument

Commemorated in 1924, Fort Matanzas National Monument is a United States National Monument run by the National Park Service. The Monument consists of a 1740 Spanish fort, Fort Matanzas, and about 100 acres of salt marsh and barrier islands along the Matanzas River on the northern Atlantic coast...

 in the 18th century to control access to the river from Matanzas Inlet, about 14 miles (22.5 km) south of St. Augustine.

The Matanzas River supports an extensive tidal marsh

Salt marsh

A salt marsh is an environment in the upper coastal intertidal zone between land and salt water or brackish water, it is dominated by dense stands of halophytic plants such as herbs, grasses, or low shrubs. These plants are terrestrial in origin and are essential to the stability of the salt marsh...

 habitat. Extensive conservation efforts including the Matanzas marsh, Faver-Dykes State Park

Faver-Dykes State Park

Faver-Dykes State Park is a Florida State Park located 15 miles south of St. Augustine, near the intersection of I-95 and US 1, and bordering Pellicer Creek, a designated state canoe trail. Activities include fishing, picnicking, boating, canoeing, camping and wildlife viewing.Among the wildlife of...

, Princess Place preservation area, Pellicer Place preservation area, Pellicer Creek Aquatic Preserve, the Guana Tolomato Matanzas National Estuarine Research Reserve

Guana Tolomato Matanzas National Estuarine Research Reserve

Guana Tolomato Matanzas National Estuarine Research Reserve on Florida's First Coast is part of a network of 26 protected coastal areas along the United States coast from Alaska to Puerto Rico, The National Estuarine Research Reserve System...

, and the Moses Creek conservation area have been established to preserve the ecosystem

Ecosystem

An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....

. The preserved areas include salt marsh

Salt marsh

A salt marsh is an environment in the upper coastal intertidal zone between land and salt water or brackish water, it is dominated by dense stands of halophytic plants such as herbs, grasses, or low shrubs. These plants are terrestrial in origin and are essential to the stability of the salt marsh...

es, mangrove tidal wetlands, oyster bars, estuarine lagoons, upland habitat, and marine environments. The Matanzas River faces several pollution issues, mostly related to urbanization

Urbanization

Urbanization, urbanisation or urban drift is the physical growth of urban areas as a result of global change. The United Nations projected that half of the world's population would live in urban areas at the end of 2008....

 in St. Augustine and the northern portion of Anastasia Island.

Two major bridges cross the Matanzas River, the Bridge of Lions

Bridge of Lions

The Bridge of Lions is a bascule bridge that spans the Intracoastal Waterway in St. Augustine, Florida. A part of State Road A1A, it connects downtown St. Augustine to Anastasia Island. A pair of Medici lions made of marble guard the bridge, begun in 1925 and completed in 1927 across Matanzas Bay...

 and the Mickler-O'Connell Bridge, both between St. Augustine and Anastasia Island.

The Matanzas River was named by Spanish forces for a massacre, led by Pedro Menéndez de Avilés

Pedro Menéndez de Avilés

Pedro Menéndez de Avilés was a Spanish admiral and explorer, best remembered for founding St. Augustine, Florida in 1565. This was the first successful Spanish foothold in La Florida and remained the most significant city in the region for several hundred years. St...

 of Spain, of a group of several hundred shipwrecked French

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

 Huguenot

Huguenot

The Huguenots were members of the Protestant Reformed Church of France during the 16th and 17th centuries. Since the 17th century, people who formerly would have been called Huguenots have instead simply been called French Protestants, a title suggested by their German co-religionists, the...

s from Fort Caroline

Fort Caroline

Fort Caroline was the first French colony in the present-day United States. Established in what is now Jacksonville, Florida, on June 22, 1564, under the leadership of René Goulaine de Laudonnière, it was intended as a refuge for the Huguenots. It lasted one year before being obliterated by the...

, led by Jean Ribault

Jean Ribault

Jean Ribault was a French naval officer, navigator, and a colonizer of what would become the southeastern United States. He was a major figure in the French attempts to colonize Florida...

. The Huguenots were executed somewhere near the present site of Matanzas Inlet in 1565. Menéndez had been ordered to kill all Protestants he found in the New World. "Matanzas" means "killings" or "slaughters" in Spanish

Spanish language

Spanish , also known as Castilian , is a Romance language in the Ibero-Romance group that evolved from several languages and dialects in central-northern Iberia around the 9th century and gradually spread with the expansion of the Kingdom of Castile into central and southern Iberia during the...

. Matanzas is thus the tenth oldest surviving European place-name in the U.S.