Question: When did Orlando SeaWorld open?
About the article "SeaWorld", section "SeaWorld Orlando".

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When founded in 1964, SeaWorld San Diego was the first of its kind to feature a Dolphin Cove.
In 1970, the second park SeaWorld Ohio was built in Aurora, Ohio, near Cleveland; it featured a Dolphin Cove.
In 1973, the third Dolphin Cove opened together with SeaWorld Orlando.
In 1988, the fourth Dolphin Cove in SeaWorld San Antonio opened its doors.
In January 2001, SeaWorld Ohio was sold to Six Flags resulting in the exhibit's closure. 
SeaWorld was founded in March 21, 1964 by four graduates of the University of California, Los Angeles.
Although their original idea of an underwater restaurant was not feasible at the time, the idea was expanded into a marine zoological park along the shore of Mission Bay in San Diego.
After an investment of about $1.5 million, the park opened with 45 employees, several dolphins, sea lions, and two seawater aquariums, and hosted more than 400,000 visitors in its first year of operation.
Initially held as a private partnership, SeaWorld offered its stock publicly in 1968 enabling them to expand and open additional parks.
The second SeaWorld location, SeaWorld Ohio, opened in 1970, followed by SeaWorld Orlando in 1973 and SeaWorld San Antonio (the largest of the parks) in 1988.
SeaWorld Ohio was later sold to Six Flags in January 2001.
The parks were owned and operated by Harcourt Brace Jovanovich between 1976 and 1989, when they were purchased by Anheuser-Busch Companies, Inc. After Anheuser-Busch was acquired by InBev, SeaWorld San Diego and the rest of the company's theme parks were sold to the Blackstone Group in December 2009, which operates the park through its SeaWorld Parks & Entertainment division.
SeaWorld currently leases the land from the City of San Diego with the lease expiring in 2048.
The premises must be used as a marine mammal park, and no other marine park may be operated by SeaWorld within 560 miles of the City limits. 
The name was first used for a water park when SeaWorld founder George Millay opened his first water park Wet 'n Wild Orlando in Orlando, Florida in 1977.
Millay went on to open six more water parks under the same name in the United States, Brazil and Mexico.
In 1997 and 1998, Millay sold the water parks to various owners including Universal Parks & Resorts, Palace Entertainment and private companies for a total of $77 million. 
Halloween Spooktacular is run inside the SeaWorld Orlando park and the SeaWorld San Diego park. 
SeaWorld was opened in 1964 by Milton C. Shedd, Ken Norris, David Demott, and George Millay.
The four graduates of UCLA originally set out to build an underwater restaurant and marine life show.
When the underwater restaurant concept was deemed unfeasible, they scrapped those plans and decided to build a park instead, and SeaWorld San Diego was opened on March 21, 1964.
With only a few dolphins, sea lions, 6 attractions and , the park proved to be a success and more than 400,000 guests visited in the first 12 months.
After considering other locations in the midwest, including the Lake Milton/Newton Falls area west of Youngstown, Ohio, it was decided that Aurora, Ohio would be the new home of a SeaWorld.
The Aurora site was approximately northwest of the Lake Milton site, and southeast of Cleveland.
By this time the founders of the company had captured a few more species of animals, including a killer whale that was brought to the new facility.
The harsh winter climate permitted the park to be open only from mid-May until mid-September.
The Walt Disney World Resort in Orlando, Florida opened near the end of the second operating season of SeaWorld of Ohio.
The success of Disney in Orlando provided a location that was already popular with tourists.
SeaWorld Orlando opened in 1973.
Harcourt Brace Jovanovich, Inc. (HBJ) purchased the company in 1976 and 12 years later they began a venture in Texas.
In 1988, SeaWorld San Antonio opened just a few miles outside of San Antonio.
Growth has pushed the city outwards, and now SeaWorld San Antonio lies in the Westover Hills community in West San Antonio.
The park was open year-round like its sister parks in California and Florida in 1988 and 1989, then went to a seasonal schedule.
The stress and financial resources it took to build and maintain a state-of-the-art marine mammal facility in the late '80s eventually took its toll on the company.
HBJ, whose primary focus was producing school books, needed to reduce its assets in order to avoid a bankruptcy.
The Anheuser-Busch Company made an offer to purchase the SeaWorld parks.
However, HBJ also owned and operated two other parks, Cypress Gardens and Boardwalk and Baseball, and out of fear of not being able to find a buyer for the two other parks, HBJ refused to sell the parks individually.
Despite a long negotiation, Anheuser-Busch bought all six parks in 1989: SeaWorld in San Diego, Aurora, Orlando and San Antonio as well as Cypress Gardens in Winter Haven and Boardwalk and Baseball in Haines City.
Soon after the sale was final, Busch sold Cypress Gardens to the park's management and closed Boardwalk and Baseball.
Anheuser-Busch put millions of dollars back into the parks to revive and to prolong their longevity.