Sources include: The Salem News, The Cincinnati Enquirer, The Evening Independent (Massillon, OH), The Evening Review (East Liverpool OH), The York Dispatch (York, PA), The Pittsburgh Press, The Akron Beacon Journal, The Cumberland News, The Dayton Herald and The Pittsburgh Post-Gazette.
Timeline compiled by Michael Gonzalez for the regional historical website .
- September 3, 1937 - Engineers place stakes on a 140-acre tract of land for construction of a racing plant north of Arroyo WV to be known as Waterford Downs. A. J. Boyle, President of the Charles Town Jockey Club, is sponsor of the project which he says is expected to be completed for a spring racing program in 1938.
- October 20, 1937 - A charter issued by the Secretary of State of West Virginia to Waterford Downs, Incorporated with principal office at Charles Town WV and chief place of business in Grant District Hancock County, West Virginia.
- May 17, 1938 - Options on 140-acres of farm land in Arroyo district have been recorded. The land includes part of farms of Jacob and Margaret Brenneman, Lee and Carrie Cline and Rudolph Marchal. The holdings include a 14,000 barrel fruit house, 2 houses, a 100-year-old house erected by Jacob Nessly and considered a landmark in Hancock County, an apple orchard and meadowlands. The section of land from the old Nessly Farm was once part of a 2364-acre farm granted by the United States government to Revolutionary War Veteran Nessly for distinguished service and signed by Patrick Henry and Benjamin Harrison on behalf of the State of Virginia. When interviewed in 1951, A. J. Boyle claimed it took 2 years to clear the obscure title to the property.
- November 18, 1938 - Construction of Waterford Downs will begin next spring. First payment on a 146-acre tract of riverfront property has been made. It is hoped a 36 day meet will be run immediately following the meet at Detroit next September.
- November 7, 1939 - Waterford Downs has been designed by the experts of Buckler and Fenhagan architects of Baltimore, MD. A Pennsylvania railroad station will be less than 200 feet from the Grandstand where escalators will be used to carry Pennsylvania railroad customers up the 40-foot slope to the plant.
- June 19, 1940 - Another 52-acre tract of land belonging to Jacob Brenneman has been purchased for $22,995. Oil leases must be cleared before other property can be bought. It is hoped for work to begin on the track this summer.
- January 2, 1942 - Headline reads "Waterford Downs Soon To Be Built". The track will be laid out and given a year to settle. Priority for steel due to World War II will cause a delay of at least a year in construction of the Grandstand, Clubhouse, Steeplechase and Barn area.
- July 18, 1946 - Pre-War plans revived for Waterford Downs. Bids are being accepted for the clearing, grading and surfacing of the new track. Bids are also being accepted for sewage, concrete and steel work.
- January 31, 1947 - Work has been halted on the Waterford Downs racing plant pending the West Virginia Assembly's final action on a proposal to increase state taxation of a track owner's share of pari-mutuel receipts.
- October 17, 1947 - Negotiations for the sale of the under construction Waterford Downs and Charles Town racetracks to the William du Pont interests are ongoing.
- August 10, 1948 - One third of the steel framework has been erected along with the skeleton of the octagon paddock and the foundation and pillars of the Clubhouse. The first barns have also been built. It is hoped the inaugural meeting could begin on Labor Day of 1949.
- April 5, 1949 - Pittsburgh Post-Gazette article states there is confusion of when Waterford Downs will open. The track reports opening day is still scheduled for Labor Day but behind the scenes officials are stating off the record that building difficulties will likely delay the opening until 1950.
- March 28, 1950 - The new mile track in West Virginia will be known as Waterford Park and not Waterford Downs. The track will open this fall.
- April 6, 1950 - Opening of the Waterford Park horse racing plant at nearby Arroyo, WV scheduled this fall will likely be postponed until 1951 because of delay in the improvement of West Virginia State Highway 66 (later renamed Route 2). This would be the final delay.
- May 19, 1951 - Waterford Park opens with 24,190 people in attendance. The first race is won by a horse named Handle who is owned by Sylvester Rich, trained by Henry Virginia and ridden by W. E. Snyder.
- May 29, 1951 - Waterford Park hosts "Ed Sullivan Day"
- June 14, 1951 - 76-year-old trainer H. Guy Bedwell wins the final race of his career at Waterford Park. Bedwell trained the first Triple Crown winner Sir Barton in 1919. Both Bedwell and Sir Barton are members of Racings Hall of Fame.
- July 2-3, 1951 - Waterford Park's first leading jockey, Howard Craig, wins 8 consecutive races. The final 6 on the July 2nd card and the first 2 on the July 3rd card.
- October 14, 1952 - Jockey Bill Hartack wins the first race of his career at Waterford Park. The Hall of Fame jockey would go on to win the Kentucky Derby on 5 occasions (1957, 1960, 1962, 1964 and 1969) which ties him for most wins by a jockey.
- October 16, 1952 - Massive barn fire during the afternoon races results in deaths of 12 horses and 1 groom. 40% of the barn area is destroyed.
- June 12, 1954 - Trainer Willard Proctor wins the Iron City Handicap with a horse named Pictus. Proctor would later train 23 graded stakes winners mostly on the Southern California circuit.
- October 28, 1957 - Waterford Park is sold to James F. Edwards and his associates the Tweel brothers of Huntington WV and Cleveland horse owner Roy Markus by original owner A. J. Boyle. One condition of the sale is that the new owners will not change the name. Boyle, who had been in poor health, dies of a heart attack on November 1.
- June 4, 1958 - Opening day on a Wednesday afternoon attracts 6,177 people who wager $333,302 a then record for a weekday handle. That handle would be equivalent to $3,155,302 in 2021 dollars.
- June 19, 1958 - Turf Racing makes it debut at Waterford Park.
- July 30, 1959 - Hall of Fame jockey Eddie Arcaro makes a special appearance at Waterford Park and is winless on 4 mounts.
- August 17, 1961 - Eddie Arcaro's 2nd appearance at Waterford Park results in a win.
- July 4, 1963 - Jockey Floyd Green wins 6 races on the card.
- August 22, 1963 - Jockey Ray Cooper wins 5 races on the card.
- December 21, 1963 - Fire destroys the original Clubhouse, which had been under renovation, causing $500,000 in damage. Frozen water lines and freezing temperatures hamper firemen who are able to save the adjoining Grandstand. There were no injuries as the track had closed for the season and other employees were dismissed the day prior for Christmas break.
- April 26, 1965 - After 14 years of daylight racing, Waterford Park holds its first card of night racing with a 7:15PM post time.
- July 23, 1965 - The brand new $1.6 million dollar Clubhouse is open to the public which includes the members only Cap and Whip Club.
- December 15, 1966 - Bill Hartack returns for a day in his honor and wins with 2 of his 3 mounts.
- March 30, 1968 - Brandys Play, a horse trained by Cecil Rogers and ridden by Ray Cooper, wins his 11th race in a row. A Waterford Park record for consecutive wins.
- May 30, 1968 - The Waterford Bath & Tennis Club holds its Grand Opening.
- November 13, 1968 - Barn L fire results in loss of 23 horses and one barn.
- January 17, 1969 - Waterford Park, Wheeling Downs, Scarborough Downs and Fairmount Park are sold to Ogden Corp of New York. James Edwards becomes a majority stockholder and is elected to the Board of Directors. Edwards' association with the tracks ends in February of 1972 when he retires as President and Chairman of the Board of Ogden Recreation.
- March 8, 1969 - Barbara Jo Rubin becomes the first female jockey to ride and win at Waterford Park. 2 weeks prior she had become the first female jockey to win at a recognized racetrack in the United State having accomplished the feat at Charles Town.
- December 9, 1969 - Kathy Kusner, the woman who broke the barrier in becoming the first licensed female jockey in the country, makes an appearance at Waterford Park. Her 3 mounts finish off the board.
- April 15, 1970 - Jockey Linda Richmond rides her first race at Waterford Park becoming the 4th female jockey in the tracks history. She rides the final race of her career on July 8, 2002 at Mountaineer.
- July 4, 1970 - Airplane crash during the evening card involving jockey Anthony Agnello who escapes without serious injury. The plane clips a power line and lands in a wooded area behind the Airco plant (now Marsh Bellofram). A crowd of over 8,000 people are sent home as power to the track is interrupted. The crash leads to the Federal Aviation Agency closing the Waterford Park landing strip shortly thereafter.
- September 2, 1971 - Cheryl White rides to victory on the horse Jetolara becoming the first African-American female jockey to win a thoroughbred race in the United States.
- June 24, 1973 - Waterford Park amphitheater opens with "A Country Jamboree Outing". Lynn Anderson, Boots Randolph and Danny Davis & The Nashville Brass play before 2171 people.
- July 8, 1973 - "Music in the Hills" rock concert at the Waterford Park amphitheater attended by an estimated 35,000-40,000 people. Humble Pie, Black Oak Arkansas, J. Geils Band and Frampton's Camel perform during the 5-hour concert.
- July 19, 1973 - Chester and Newell residents meet at the Newell United Methodist Church to organize their efforts to block the August 12 concert planned at Waterford. The concert was to feature the Edgar Winters Group and the rock band Focus. Later the groups Foghat and Spooky Tooth were added to the lineup.
- August 7, 1973 - Judge Callie Tsapis refuses to lift an injunction she had issued against the August 12 concert. Concerns included traffic congestion, inadequate parking and sanitation facilities at the July 8 concert. The concert would never take place.
- December 31, 1973 - The year ends with Dale Baird taking national training honors with 305 winners. The first time any trainer has passed the 300 win mark. He also won the 1971 national title with 245 winners.
- March 9, 1977 - Waterford Park hosts Earnie Shavers night. Shavers held his training camp in nearby Calcutta, OH and would lose a 15-round decision to Muhammad Ali for the Heavyweight title on September 16, 1977.
- August 18, 1977 - Trainer Frank Whiteley, Jr. is honored at Waterford Park as part of a celebration promoting the West Virginia Derby. Whiteley trained champions Ruffian, Forego, Damascus, Tom Rolfe and Chieftain. It is Whiteley's first visit to Waterford Park since he ran horses here in 1952. The following year Whiteley is inducted into the Racing Hall of Fame.
- August 20, 1977 - Star studded lineup including Jockeys Steve Cauthen and Angel Cordero, Jr. and Trainers Laz Barrera and Grover "Bud" Delp headline the West Virginia Derby. All 4 are Thoroughbred Racing Hall of Famers. However, it is jockey Vince Bracciale, Jr., a West Virginia native who rode at Waterford Park early in his career, who steals the show as the winning jockey.
- August 21, 1978 - Future Hall of Fame jockeys Pat Day and Craig Perret run first and second in the 19th Renewal of the West Virginia Derby.
- February 24, 1979 - Trainer J. C. Williams sets a national training record as his runners win 8 of 12 races on the card.
- August 20, 1979 - Jockey Patti Cooksey wins her first career race at Waterford Park. In 1985, she became the first female jockey to ride in The Preakness.
- December 31, 1979 - Dale Baird wins his 5th national training title of the decade. In 1979, he also becomes the first person since 1949 to win both national titles as an owner and as a trainer with totals of 243 and 317 respectively. His horse Little Chuck ties for winningest horse in the country with 12 wins.
- May 29, 1980 - Jockey Miguel Jimenez wins with 5 of his 7 mounts.
- January 31, 1982 - Waterford Park holds its first Sunday afternoon racing program.
- January 2, 1983 - Due to economic pressures, layoffs in the steel industry, competition from lotteries and competition from the thriving Wheeling Downs dog track, Waterford Park will close for 3 months. The barn area will be cleared out for the first time in 16 years.
- March 30, 1983 - Waterford Park reopens for the 1983 season.
- July 4, 1983 - Jockey Rick Markham wins 8 races on the doubleheader card while narrowly missing on 2 others by a head and a nose.
- November 13, 1983 - Continuing to lose money Waterford Park closes on short notice. The meet was expected to run until November 27.
- May 18, 1984 - Waterford Park reopens. A tax break eliminates the percentage Waterford Park pays to the state and replaces it with a flat $2,000 takeout. It is estimated this will save the track $1.3 million a year.
- November 23, 1984 - Trainer Dale Baird wins his 4000th race as a trainer.
- May 14, 1987 - The West Virginia Racing Commission has approved the sale of Waterford Park to Bill Blair of New Springfield, OH. Blair also buys the adjoining Waterford Inn from Ogden Corp.
- June 29, 1987 - The final racing card is held at Waterford Park. The last winning horse "Earth Design" is owned and trained by longtime Waterford Park trainer Tony Polichena.
- June 30, 1987 - Effective this day Waterford Park changes its name to Mountaineer Park. The first card as Mountaineer Park is held on July 3, 1987.