The Port of Houston is the port of Houston, Texas, the fourth-largest city in the United States. The Port is a 25-mile-long complex of diversified public and private facilities located a few hours' sailing time from the Gulf of Mexico. It is the busiest port in the United States in terms of foreign tonnage, second-busiest in the United States in terms of overall tonnage, and tenth-busiest in the world. 
The port is made up of the port authority and the 150-plus private industrial companies along the Houston Ship Channel and Galveston Bay; many oil companies have built refineries on the channel where they are protected from the Gulf of Mexico. The petrochemical complex associated with the Port of Houston is one of the largest in the world.
The original Port of Houston was located at the confluence of Buffalo Bayou and White Oak Bayou in downtown Houston by the University of Houston–Downtown. This area is called "Allen's Landing" and is now a park. It is the birthplace of the City of Houston.
Shipping points grew at multiple locations on the Buffalo Bayou including the port of Harrisburg (now part of Houston) and the docks on the Allen Ranch. By the end of the 19th century Buffalo Bayou had become a major shipping channel with traffic beginning to rival Galveston.
The citizens of Harris County approved creation of the modern port in 1909, believing that an inland port would better serve the region after the destructive Galveston Hurricane of 1900. President Woodrow Wilson officially opened the port to traffic as the World Port of Houston and Buffalo Bayou on November 10, 1914. Early supporters would prove to be correct; the port has grown to be one of the world's largest, while the nearby Port of Galveston has dwindled in significance.
Approximately 215 million tons of cargo moved through the Port in 2005, about half of which was containerized cargo. The Port has three separate terminals dedicated to the handling of cargo containers: Barbours Cut (at Morgan's Point), Galveston East End (leased from the Port of Galveston, the Port's long-time rival), and Bayport (in Pasadena, opened in October 2006). The Barbours Cut terminal was, in fact, the port's first terminal specifically designed for these shipments. Additional general cargo terminals include Terming Basin, Jacintoport, Woodhouse, and Care.
The Port offers a 90-minute free cruise aboard the M/V Sam Houston, details of which can be found on its website. Since the Houston Ship Channel is closed to recreational traffic, this is the only means by which the general public can view port operations, and thus the tours are highly popular. Tours are available daily except on Mondays, holidays, and the entire month of September (when the vessel undergoes maintenance).
The Port is operated by the Port of Houston Authority, an independent political subdivision of the State of Texas. The Authority is governed by a seven-member Commission. The City of Houston and the Harris County Commissioners Court each appoint two commissioners; these two governmental entities also jointly appoint the chairman of the Port Commission. The Harris County Mayors & Councils Association and the City of Pasadena each appoint one commissioner. Daily operations are overseen by an Executive Director who serves at the will of the Commission.
Despite being one of the youngest major Ports in the world (the Port will not reach its 100th birthday until 2014) it has already racked up an impressive list of firsts.
Most notable firsts include: