The major leagues have never seen anything like Coors Field. Offense gets boosted from every direction: The light air helps fly balls carry 20-40 feet further; lower air resistance reduces the snap on breaking balls; dry conditions make balls harder and bouncier; and deep fences, aimed to ameliorate all this, create acres of fair territory in which more balls can fall in for singles and doubles. The result? A lifetime STATS Inc. park index of 155 -- meaning runs score at Coors at a rate 55 percent higher than its contemporaries, by far the highest in major-league history.

Still, it's not the only hitters park around, past or present. Using the STATS Inc. park factors, here are the top 10 hitters parks that saw substantial portions of their lives after the emergence of modern offense in 1920:

1. Baker Bowl
When: 1895-1937, Philadelphia Phillies.
Lifetime Park Index: 114.
History: Rebuilt for 1895 after fire raged through the originally wooden park, Baker Bowl featured its era's Green Monster, a 40-foot high wall and screen in right field that stood just 281 feet down the line, more importantly 310-320 to the power alley. (This forced the right fielder to play so close to the infield that Red Smith quipped, "If the right fielder had eaten onions at lunch, the second baseman knew it.") It's amazing that Grover Cleveland Alexander, a Hall of Fame right-hander, put up most of his best years as a Phillie. Just as oddly, it was after a screen was added to raise the fence height to 60 feet in 1929 that the numbers for which we most remember Baker Bowl were achieved. That year, Lefty O'Doul hit .398 with 254 hits. The next season, Chuck Klein hit .386-40-170, and the Phillies hit .315 as a team. In 1933, Klein won the triple crown at .368-28-120. Alas, the Phillies were consistently dreadful during this period, finishing last or close to it almost every year.

2. Fenway Park
When: 1934-present, Boston Red Sox.

	The Red Sox are not opposed to Monster revisions.

Lifetime Park Index: 112.
History: Originally built in 1912, and a pitchers' park while housing four World Series champions during its first decade, Fenway was rebuilt by new owner Tom Yawkey for the 1934 season and added its most distinctive and enduring feature -- the 37-foot-high Green Monster -- in 1936, to protect the shop windows on Lansdowne Street. It immediately became a hitters' park, with right-handed batters popping short flies over the wall and left-handers poking line drives off it. (This helped hide the fact that Fenway's right-field fair territory has actually been quite immense, with a 302-foot foul line almost immediately falling back to 370-380 feet, causing many flies that would easily clear Yankee Stadium's fences to fall safely into the gloves of Jackie Jensen and Dwight Evans.) Summer breezes from home toward the outfield also boosted offense. In light of all this, Fenway has always invited extra scrutiny of individual batting statistics ranging from Ted Williams -- in comparisons to Joe DiMaggio -- to Fred Lynn and Jim Rice. The effects appear to have been dulled, though; construction of the 600-level suites in the early '80s, which altered Fenway's wind patterns, seems to have dulled the park's offensive excitability. It now plays pretty average.

3. Atlanta-Fulton County Stadium
When: 1966-96, Atlanta Braves.
Lifetime Park Index: 112.
History: In a way, this was major-league baseball's first experiment in playing at altitude -- the park stood 1,050 feet above sea level, highest in the majors. Despite normal fence distances (330-385-402-385-330 after a bit of a boost in the 1970s), the light air appeared to particularly help left-handed hitters, though the Braves typically had only a few such starters, like Ralph Garr and Darrell Evans. (Had advanced sabermetrics been around during that time, perhaps they would have had more.) As for premonitions of Coors, the Braves caused a sensation by having three 40-homer hitters -- Davey Johnson, Darrell Evans and Hank Aaron -- in 1973, one year after San Diego's Nate Colbert slammed five home runs in a doubleheader in Atlanta. In 1986, Bob Horner hit four home runs in one game there, only to watch his team lose 11-8.

4. Metropolitan Stadium
When: 1961-81, Minnesota Twins.
Lifetime Park Index: 108.
History: Players still talk about rocks the size of thumbnails populating the infield dirt, but the Met combined 815 feet of altitude with a 360-foot foot fence in left-center field that boosted offense during a relatively down era for baseball offense, specifically the 1960s. Though home-road data is sketchy, the park probably helped Harmon Killebrew, Bob Allison, Earl Battey and others boost their numbers, though nothing like Coors Field does today. (Though in June 1966 the Twins hit five home runs in an inning, a grotesque display of power at the time.) The Twins fled the Met in 1982, and the Bloomington site on which the park once stood now houses the Mall of America. Minnesotans now watch their baseball at another hitters park, the ...

5. Hubert H. Humphrey Metrodome
When: 1982-present, Minnesota Twins.
Lifetime Park Index: 108.
History: The Twins' new home played quite like its old one, despite conditions that were anything but similar. The indoor park, whose roof is supported by pumped-in air pressure, features air currents that reportedly aid fly balls. There is also precious little foul territory and a fantastic hitting background. (Kent Hrbek was a notable beneficiary, posting a lifetime .906 OPS in the dome and just .798 on the road.) The park hasn't allowed home runs quite like it used to lately, but offense remains robust. Perhaps the Rockies should use the Twins as inspiration: In 1987, the team had a great record (56-25) at home, was horrible on the road (29-52), but still won its first World Series title.

6. Sportsman's Park/Busch Stadium
When: 1909-1966, St. Louis Browns/Cardinals.
Lifetime Park Index: 107.
History: The home of the Browns starting in 1902, the first incarnation of Sportsman's Park was rebuilt after the 1908 season to become the stadium known for most of the 20th century. The Cardinals moved in in 1920 and stayed after the Browns moved to Baltimore in 1954. (The 33-year cohabitation was the longest in major-league history.) Its most notable feature for most of its existence was a Baker Bowl-esque, 33-foot wall in right field that stood just 310 feet down the line and 348 feet in the alley. Ty Cobb had his only three-homer game here, at the age of 38. Rogers Hornsby and George Sisler posted five .400 batting averages during the roaring 1920s, and Joe Medwick won the Triple Crown in 1937, though home-road splits aren't available yet to help us gauge the park's effects on them. A screen was added to the right-field wall in 1930 to curb cheap home runs and might have had its greatest effect two years later, when Philadelphia's Jimmie Foxx hit 58 home runs but reportedly had 12 homers stopped by the St. Louis screen. (Reportedly.) For all of Sportsman's Park's hitting exploits, it might be remembered most for its non-power moments: It was home to one-armed Pete Gray, midget Eddie Gaedel, and Enos Slaughter's Mad Dash to win the 1946 World Series.

7. Exhibition Stadium
When: 1977-88, Toronto Blue Jays.
Lifetime Park Index: 107.
History: This stadium's first game found snow covering the park and was originally built for football -- remember how the gridiron extended well beyond the right-field fence? -- but attempted to house the expansion Blue Jays for their first dozen seasons. It generally helped hitters, particularly in its early years. (Heck, that first game saw noted slugger Doug Ault hit two homers and Al Woods go deep in his first big league at-bat.) The next season, the Blue Jays drubbed Earl Weaver's Orioles 24-10. Young hitters such as Jesse Barfield, Lloyd Moseby and Willie Upshaw benefited from the park, Barfield to a ridiculous degree in 1983: .304-22-49 at home, .193-5-19 on the road. Under appreciated ace Dave Stieb was naturally hampered, posting a career ERA one-third of a run lower when away from Exhibition Stadium.

8. Wrigley Field
When: 1916-present, Chicago Cubs.
Lifetime Park Index: 105.
History: Originally built for the Federal League and named Weeghman Park, the stadium soon had its name changed by Cubs owner (and chewing-gum magnate) William Wrigley Jr. and became known for masticating pitchers. It first had longer fence distances than we know today -- generally about 10 feet deeper -- but they got trimmed back over 20 years as the small park underwent renovations to increase capacity. It was then that offense really boomed, particularly during all those day games when the wind blew out. Who can forget those classic Cubs-Phillies tilts in the late '70s, with scores like 18-16 (with four Mike Schmidt home runs) and 23-22? Of course the Cubbies didn't win too many of those slugfests. In 1975 they lost to the Pirates 22-0 as Rennie Stennett went 7-for-7.

9. Municipal Stadium
When: 1955-67 Kansas City A's, 1969-72 Kansas City Royals.
Lifetime Park Index: 105.
History: The Kansas City Athletics adapted its city's former American Association and Negro League park for major-league play when arriving from Philadelphia in 1954, though the A's play was major league in name only; they had losing records each of their 13 years. The park had relatively normal dimensions but still helped hitters, Vic Power and Bob Cerv (.305-38-104 in 1958) among them. Then again, nothing helped sluggers like Roger Maris more than being invariably traded to the Yankees. (New owner Charlie Finley tried to reverse the trend in 1964 by moving the right-field fence 296 feet from home plate, the same as Yankee Stadium, but was stopped by disapproving major-league officials.) Finley bolted a few years later. The Royals called the old park home for their first four years before moving to turf-covered, doubles-and-triples Royals Stadium in 1973.

	The quirks at Tiger Stadium include the right-field overhang.

10. Briggs/Tiger Stadium
When: 1938-99, Detroit Tigers.
Lifetime Park Index: 104.
History: Using money from the Tigers' winning two pennants and the 1935 World Series, Detroit's old Navin Field was completely rebuilt into Briggs Stadium for the 1938 season and promptly saw Hank Greenberg slam 58 home runs. (That wasn't exactly a fluke for Greenberg, though -- he had driven in 170 and 183 runs the previous two years.) Although its center-field fence stood a whopping 440 feet away, a second deck throughout right field that jutted 10 feet into fair territory could make the park a hitter's paradise. The Yankees and Tigers combined for 11 home runs in one game in June 1950, and two of the most famous All-Star Game home runs came there off the bats of left-handed hitters: Ted Williams' three-run shot to win the 1941 game, and Reggie Jackson's monster blast off the light tower against Dock Ellis in 1971.

Alan Schwarz is the senior writer of Baseball America magazine and a regular contributor to ESPN.com.