- Dentzel Carousel constructed by Dentzel Carousel Company in Philadelphia, PA.
- Angus Wynne opens Six Flags over Texas in Arlington under the banner of his company, The Great Southwest Corporation.
- Angus Wynne sells GSC, including Six Flags, to Penn Central Railroad Corp.
- Judge Roy Hofheinz (former county judge, Houston mayor (1952-1955),
and Houston Astro's team owner) opens Astroworld, Houston's first
major theme park. The eight themed areas consist of: Alpine Valley, American, Children's World, European Village, Modville, Plaza de Fiesta, Oriental Corner, and Western Junction.
Original attractions included 610 Limited Train, Alpine Carousel, Alpine Sleigh Ride (dark ride through Der Hohfheinzberg Mountain), Astroway (VonRoll Sky Cars), Astrowheel (double ferris wheel), Barnyard Petting Zoo, Black Dragon (spider/monster ride)
Crystal Palace Theater, The Happening (scrambler), Le Taxi (later Antique Taxis)
Lost World Adventure (jungle boat ride through Rio Misterio), Maypole (tea cups), Mill Pond (bumper boats)
Shooting Gallery, Skyrama (later Astroneedle), Spinout (car ride),
Rub-a-Dub (nursery rhyme themed boat ride), Wagon Wheel (Chance trabant)
- Astroworld's grand opening: June 1, 1968.
- Bamboo Shoot log flume opens in Oriental Village.
- The Serpent, a junior steel children's coaster, opens as Astroworld's first rollercoaster in Oriental Village.
- Fun Island themed area opens.
- Wacky Shack funhouse opens on Fun Island.
- The Happening scrambler is renamed The Orbiter and enclosed in a Modville walled structure.
- Swamp Buggy Ride (a Chance toboggan ride themed in a hollow tree) opens on Fun Island.
- Barrel of Fun rotor ride added to Modville.
- Mod Shop opens in Modville.
- Country Fair themed area opens.
- Dexter Freebish Electric Roller Ride, a steel mine train rollercoaster, opens in Country Fair.
- Country Fair Carousel and The Nickelodeon and Horseless Carriage Pavilian museum opens in Country Fair.
- Der Fender Bender bumper cars open in County Fair.
- Marvel McFey, Astroworld's official mascot, debuts.
- Seal Pond added to Children's World.
- Swamp Buggy removed.
- Marvel McFey theater opens in Childrens's World.
- "Dancing Waters" and "Fantasy of Fire" shows added to the Lagoon Theater.
- Concert stage constructed at the base of the Skyrama.
- Gunslinger swinging chair Yo-Yo ride opens at site of Mill Pond.
- Mill Pond removed.
- Six Flags Corporation leases Astroworld.
- Coney Island themed area opens.
- Airena Theater opens in Coney Island.
- Astroworld Season Passes debut this season.
- Lost World River Adventure renamed The River of No Return.
- The Texas Cyclone wooden twister rollercoaster opens June 12, 1976.
- Horizons Theater opens in old Orbiter structure.
- The Orbiter renamed Runaway Rickshaws and moved to Oriental Village.
- Black Dragon moved from Oriental Corner to Coney Island, renamed Razzmatazz.
- Maypole removed.
- Rub-a-Dub is removed.
- Bamboo Shoot renovated, given new control mechanisms.
- Seatbelts added to last car in Texas Cyclone.
- Aquarena Theater built with dolphin performances (Skipper and Dolly).
- Boogie Fog Disco added to Country Fair area.
- Country Fair Carousel removed.
- Modville area renamed International Plaza.
- Seatbelts added to all Texas Cyclone seats.
- Greezed Lightnin', a Schwarzkopf shuttle loop, opens in Western Junction.
- Razzmatazz is removed.
- Whirling Dervish flying bobs added to Coney Island.
- Greezed Lightnin' railroad crossing added.
- Serpent re-profiled to remove a dip.
- Seat dividers were added to Texas Cyclone trains.
- Airena Theater enclosed and renamed Showcase Theater.
- Lagoon Grandstand opens with stunt skier performances.
- Barrel of Fun is removed.
- "A Touch of Elvis" show runs in Showcase Theater.
- Texas Cyclone re-profiled, track of south bend lowered 2 feet so train doesn't stall in high winds.
- New brake system added to Texas Cyclone.
- Air operated gates added to Greezed Lightnin' queue.
- Astroneedle receives new Intamin cabin.
- The Big Red Barn company picnic facility opens.
- Thunder River, world's first river rapids ride, opens.
- Thunder River railroad crossing added.
- Dexter Frebish rollercoaster damaged by dump trunk during Thunder River construction.
- Dexter Frebish brakes are reversed to allow quicker stopping of the train.
- Country Fair is remodeled into Nottingham Village themed area.
- Dexter Frebish Electric Roller Ride is renamed Excalibur.
- Astrowheel removed.
- Der Fender Bender renamed Joust About.
- Warp 10, a Huss troika ride, added to International Plaza.
- Astroway recieves all new cars and computer control system.
- Texas Cyclone rolling stock (PTC trains) changed following an injury lawsuit.
- Crystal Palace introduces "The Great Texas Longhorn Revue" robotic cow show.
- Showcase Theater debuts "Here's Hollywood" show.
- Joust About removed, building converted into Festhalle.
- Penn Central Sells Six Flags Corp., which manages the park to Bally Manufacturing Corporation for $140 million.
- Construction begins on WaterWorld.
- Texas Cyclone 3" and 5" wide track rails all replaced with 6" wide track rails.
- Park founder Judge Roy Hofheinz dies in November at the age of 70.
- SkyScreamer, a 10 story Intamin freefall ride, opens in Plaze de Fiesta.
- WaterWorld water park opens adjacent to Astroworld.
- Double chairs removed from Gunslinger.
- Waterworld railroad station added.
- Greezed Lightnin' track reprofiled, drive panel modified.
- Texas Cyclone transfer track modified after an employee park accident.
- XLR-8, an Arrow suspended rollercoaster, opens.
- The Alpine Sleigh Ride is closed.
- The Magical World of Marvel McFey children's area closed.
- The Enchanted Kingdom children's area opens adjacent to European Village.
- Discovery Mountain opens at site of Alpine Sleighs.
- The River of No Return removed.
- Whirling Dervish replaced by Tilt-a-Whirl.
- Spinout removed.
- Le Taxis moved to USA area, renamed Antique Taxis.
- The River Ride educational boat ride opens at site of River of No Return.
- Six Flags Corp. signs a licensing deal with Warner Communications to use Looney Tunes characters in the parks.
- Southern Star Amphitheater opens.
- Lapbar straps added to Excalibur.
- The River Ride renamed The Wetlands.
- Bugs Bunny and other Warner characters replace Marvel McFey and friends.
- Shanghai Chinese Acrobatic Troupe performs at Showcase Theater.
- Videocity dance club opened in Coney Island.
- New brake system added to Texas Cyclone.
- Looping Starship, an inverted swinging ship, replaces Warp 10 in Int'l Plaza.
- The Chonqing Chinese Acrobats perform in Showcase Theater.
- The Bugs Bunny Wonder Circus debuts in Enchanted Kingdom.
- "Fright Nights" Halloween event debuts.
- One of the original two railroad steam engine trains is sold.
- Air operated gates installed in Texas Cyclone queue.
- U.S. High Diving Team show replaces ski show.
- Laser/Fireworks show added.
- The Wacky Shack is closed.
- Warp 10 returns as Warp 2000 in Plaza de Fiesta.
- "A Midsummer Night's Scream" show plays in Showcase Theater.
- John Bull and General Electric railroad trains added.
- Texas Cyclone transfer track rebuilt as complete loop.
- The Texas Cyclone is retrofitted with new Morgan "Coffin Car" trains (following yet another injury lawsuit).
- Wesray Capital Corp. and Six Flags managers buy out the Six Flags Corp. from Bally for $610 Million.
- Tidal Wave choot-the-chutes opens in Plaze de Fiesta.
- Astroworld "Holiday in the Park" winter event debuts.
- Videocity removed.
- The Wetlands boat ride removed.
- Waterworld in-park railroad crossing constructed.
- The Viper, a Schwarzkopf looping star rollercoaster, added to Oriental Village.
- The Runaway Rickshaws moved to Knottingham Village and renamed Joust-a-bout.
- "Stars of the U.S.S.R." show premiers in Showcase Theater.
- Excalibur receives new lapbar system.
- Antique Taxis track shortened.
- Diapers added to XLR-8 (to keep oil and crud off park guests).
- Ultra Twister, a unique TOGO heartline rollercoaster, opens near European Village.
- "Ghost Town" removed from 610 Limited track.
- Filtration system added to Tidal Wave to keep water clean.
- Bugs Bunney 50th birthday celebration takes place.
- Time Warner Inc. purchases 19.5% of the Six Flags Corp. from Wesray Capital Corp. and Six Flags managers for $19.5 Million.
- The Condor, portable tower flat-ride, operates for one year in Coney Island.
- Whirling Dervish/Tilt-a-Whirl removed.
- Sid and Marty Krofft's "Blast!" show begins two year run in Showcase Theater.
- Air conditioning added to Astroneedle.
- Gunslinger receives new computer console and PA system.
- Texas Cyclone north bend smoothed and leveled, lapbar straps removed.
- Ultra Twister receives new dispatch system.
- Time Warner buys half of Six Flags Corporation after it nearly files bankruptcy due to Wesray's debt. The Blackstone Group and Wertheim Schroder buy the second one-half. Time Warner retires the debt. Six Flags Corp. is left with $150 Million in capital.
- Adventure Rivers of Texas waterslide ride added to Coney Island.
- Batman fireworks show debuts in Lagoon Theater.
- John Bull railroad train removed.
- Batman: The Escape stand-up Intamin rollercoaster opens in European Village.
- Enchanted Kingdom Discovery Mountain closes.
- Incredible Acrobats of China show plays in Showcase Theater.
- Dennis the Menace Screen Test show plays in Showcase Theater.
- "Legends in Concert" show plays in Showcase Theater.
- "Fright Nights" Halloween operation renamed "Fright Fest".
- Time Warner purchases remaining 50% of the Six Flags Corp. from investors for $70 Million.
- International Plaza themed area renamed USA.
- Batman railroad crossing added.
- Excalibur brakes reversed again.
- Plaza de Fiesta themed area renamed Mexicana.
- World Globe removed from entry fountain.
- Side guard removed from Batman trains.
- Mayan Mindbender indoor rollercoaster added to Oriental Village, replaces mini-golf course.
- Mini-Golf removed.
- Antique Taxis double tracks combined into one track.
- Ratcheting lapbars added to Tidal Wave.
- Time Warner, in an effort to reduce its own debt, sells 51% of the Six Flags Corp. to Boston Ventures. Boston Ventures would pay $200 Million and assume $800 Million of Time Warner’s debt.
- Looney Toons Land displaces the Enchanted Kingdom.
- "Batman Returns Water Stunt Show" debuts in the lagoon theater (1996-1998).
- Dungeon Drop, a 20 story free-fall ride, added to Knottingham Village.
- Joustabout scrambler removed.
- "Dive!" acrobatic diving show debuts.
- New computer system installed in Greezed Lightnin'
- XLR-8 restraints modified.
- Taz's Texas Tornado, a four loop Schwarzkopf coaster, opens in Mexicana.
- SkyScreamer is removed.
- Aquarena Theater is removed.
- Gunslinger moved 100 ft to AquaArena location, water pond filled in.
- Dentzel Carousel refurbished, given new control and drive system.
- Runaway Rickshaws scrambler returned to Oriental Village.
- On April 1, Premier Parks (PKS) purchases 100% of the Six Flags Corp. for a sum of close to $1.9 Billion (equity and debt) from Time Warner and Boston Ventures.
- "Holiday in the Park" winter operations cancelled.
- Bamboo shoot flume re-built with concrete structure.
- Viper receives new computer control system.
- Taxis railroad crossing added.
- Six Flags Houston receives $16 million capital package, the largest single year investment in the park's history (much of this is spent on Waterworld).
- Serial Thriller, a Vekoma suspended looping rollercoaster, added near Knottingham Village.
- Serial Thriller railroad crossing added.
- Serial Thriller trains dropped off transfer track, new track and bumper constructed.
- Antique Taxi track shortened and entrance moved to Coney Island to make room for Go Karts.
- Go Karts added to USA area.
- Elizabeth Diesel Hydraulic railroad train added.
- Elizabeth Diesel Hydraulic railroad train added.
- Taz's Texas Tornado renamed Texas Tornado, ability to run 5 trains reduced to 4 and new anti-rollbacks added.
- Excalibur removed.
- Wagon Wheel removed due to structural problems.
- Astroneedle is closed.
- Shooting Gallery closed.
- The last car of each Batman train was removed to make a third train.
- Adventure Rivers (closed for 3 years) is removed.
- Thunder River briefly closed after an accident at Six Flags over Texas, receives Opryland rafts.
- Batcave portion of Batman: The Escape queue is closed.
- "Fright Fest" features the only free Alice Cooper's Brutal Planet spookhouse (with Astroworld admission).
- Big Kahuna and Hook's Lagoon added to revamped Waterworld.
- The Astroneedle is removed (and not sent to Mexico).
- Wagon Wheel re-installed.
- "Rock this Country" country and western show added.
- "The Great Texas Longhorn Revue" removed.
- "Fantasy of Fire" fireworks show reinstated.
- "American Rock" performs at Showcase Theater. The Grease Monkeys sing at Juke Box Hill in USA area.
- The Big Red Barn picnic area renamed A&W Ranch.
- Alpine Clock repaired.
- Bamboo Shoot is renamed The Ozarka Splash.
- Texas Cyclone trains rebuilt for its 25th birthday, oversized headrests removed.
- New Schwarzkopf OTSR restraints installed on rebuilt Texas Tornado trains.
- FastLane reservations instated for Cyclone, Batman, Serial Thriller, and Ozarka
- Prime Time exclusive hours operation introduced.
- Showcase Theater acts include Tommy Drake, Mapapa African Acrobats, Q Productions, Radio Active, and Ken Whitener. The Grease Monkeys sing and Rockabilly bands play at Juke Box Hill in USA area. Yogi Baird (contortionist fiddler) and "Rock This Country" acts at Crystal Palace. Looney Tunes Town Big Top and "What's Up Rock?" play at Looney Tunes Theater.
- Warp 2000 painted dramatic new colors.
- Goldfish pond added to Oriental village.
- Daffy Dollars park discounts introduced.
- Anton Schwarzkopf passes away on 30 July 2001.
- Texas Tornado and Thunder River closed for most of the season.
- ACE plaque added to Greezed Lightnin'
- Thunder River re-opens.
- Nottingham games are completely gutted and revamped.
- Eurobungee opens in Mexicana.
- WaterWorld becomes themed section of AstroWorld (2 parks, now 1 ticket)
- Showcase Theatre is renamed 'Reliant Energy Showcase Theatre'.
- Pool game added to old Shooting Gallery in Western Junction.
- Quarterback Corral is replaced by a Bobs Space Racer game
- Lift of Ultra Twister is painted.
- "Gravity Hill" re-tracked on Texas Cyclone.
- Handrails along Texas Cyclone's track repainted deep red.
- Astroway cars are repainted Red, White and Blue.
- Wok-N-Roll replaces Shanghai Grill in Oriental Village.
- Yin-Yang designed into pavement in Oriental Village.
- Horizons building roof is rebuilt.
- New Landscaping for Batman Queue area.
- Foot massagers added in Western Junction.
- Water canons added to Bamboo Shoot.
- Fantasy of Fire retired, replaced with "Celebrate!" laser show.
- Humongous Pass introduced.
- "Industrial Movement" in the Showcase Theater.
- Mapapa Acrobats return for limited engagement.
- "Blazing Idiots" show added in Western Junction.
- "Rockin' Country" show added in Crystal Palace.
- "Gabby's" BBQ replaced with Western Smokehouse.
- Lift Structure of Tidal Wave rebuilt.
- "Sugar Ray" gets drunk and nearly incites riot at Southern Star.
- "Time Terror" haunted house replaced "Brutal Planet" for Fright Fest.
- XLR-8 trains 2/3rds reversed during Fright Fest, never before attempted.
- Texas Tornado removed at the end of the 2002 season and sent to Six Flags Marine World where it runs in a slightly modified form as "Zonga" (2003-2004).
- AstroWorld opens for it's 35th Season on March 8, 2003.
- Batmobile removed from AstroWorld, sent to SFNO for theming.
- Batman The Escape has loop repainted.
- Carousel Horses repainted, roof repaired.
- XLR8 receives new queue line, exit path, continues 1/2 and 1/2 operation.
- Ultra Twister has switchback (North End) repainted.
- Mayan Mindbender has seatbelts installed.
- Looping Starship has exit path redone.
- Greezed Lightnin' turns 25.
- New wooden queue rails line Thunder River.
- Chaperone Lounge added on Main Street for events.
- Mini-Loafs are offered as a 35th Anniversary treat!
- Foot Massagers added to European Village.
- Fast Lane booth removed from Main Street.
- Various Main Street buildings repainted.
- Front Gate receives new (faster) registers to help move lines.
- 2003 map revamped from previous years.
- SWAT opens.
- DIABLO FALLS opens.
- XLR-8 painted blue and orange, receives new queue canopies.
- Ultra Twister repainted Lime Green and Navy Blue.
- Batman The Escape repainted yellow and black.
- Viper tunnel repainted.
- New front gate canopy installed.
- New Six Flags AstroWorld sign is erected over front gate.
- New Six Flags welcome sign and electronic LED scroll sign added to parking toll plaza.
- Freeway side of Reliant Showcase Theatre repainted.
- Old Excalibur theming returns to Nottingham Village.
- Seat dividers added to Viper and Greezed Lightnin' trains allowing single riders.
- Ultra-Twister and Serial Thriller re-painted (same colors).
- Seatbelts removed from Diablo Falls (added to the ride in mid 2003).
- Reliant lot parking increased to $8.
- Carousel livery museum & workshop opens in Western Junction.
- Six Flags issues a press release Sept 12, 2005 announcing Astroworld's permanent closure at the end of its 37th season in an effort to reduce corporate debt.
- Astroworld's last day of operation: Sunday, October 30th, 2005.
- Six Flags stockholder revolt led by Washington Redskins owner Daniel Snyder ousts PKS management team in November.
- Former Astroworld general manager and Thunder River raft ride inspiration Bill Crandall passes away in February at the age of 62.
- Texas Cyclone demolished March 9, 2006. The landmark wooden rollercoaster would have celebrated its 30th birthday three months later.
- Six Flags announces in May an agreement to sell the former Astroworld land plot to Conroe real estate agent Angel/McIver for $77 million. No formal plans for the site are released at this time.
- Runaway Rickshaws scrambler and Warp 2000 troika relocated to Six Flags Over Texas.
- Dungeon Drop tower relocated to Six Flags St Louis.
- 1895 Dentzel Carousel purchased by Brass Ring Entertainment of Sun Valley, CA after the city of Houston fails to bid on the historic attraction.
- Greezed Lightnin' rollercoaster relocated and scheduled to open at Joyland park in Lubbock, TX.
- Mayan Mindbender rollercoaster and Gunslinger relocated and scheduled to open at Wonderland park in Amarillo, TX.