NHL outdoor games
List of NHL outdoor games

Date
Event
Site
Away team
Home team
Score
Attendance
February 2, 1954
exhibition game
Marquette Branch Prison, Marquette, Michigan
Detroit Red Wings
Marquette Prison Pirates
N/A
0
April 9, 1956
exhibition game
Conception Bay Sports Arena, Bay Roberts, Newfoundland
Boston Bruins
Bay Roberts, Brigus, Shearstown, Coley's Point (1 period each)
N/A
N/A
September 27, 1991
exhibition game
Caesars Palace, Las Vegas, Nevada
New York Rangers
Los Angeles Kings
5–2
13,007
November 22, 2003
Heritage Classic
Commonwealth Stadium, Edmonton, Alberta
Montreal Canadiens
Edmonton Oilers
4–3
57,167
January 1, 2008
Winter Classic
Ralph Wilson Stadium, Orchard Park, New York
Pittsburgh Penguins
Buffalo Sabres
2–1 (SO)
71,217
January 1, 2009
Winter Classic
Wrigley Field, Chicago, Illinois
Detroit Red Wings
Chicago Blackhawks
6–4
40,818
January 1, 2010
Winter Classic
Fenway Park, Boston, Massachusetts
Philadelphia Flyers
Boston Bruins
2–1 (OT)
38,112
January 1, 2011
Winter Classic
Heinz Field, Pittsburgh, Pennsylvania
Washington Capitals
Pittsburgh Penguins
3–1
68,111
February 20, 2011
Heritage Classic
McMahon Stadium, Calgary, Alberta
Montreal Canadiens
Calgary Flames
4–0
41,022
January 2, 2012
Winter Classic
Citizens Bank Park, Philadelphia, Pennsylvania
New York Rangers
Philadelphia Flyers
3–2
46,967
January 1, 2014
Winter Classic
Michigan Stadium, Ann Arbor, Michigan
Toronto Maple Leafs
Detroit Red Wings
3–2 (SO)
105,491
January 25, 2014
Stadium Series
Dodger Stadium, Los Angeles, California
Anaheim Ducks
Los Angeles Kings
3–0
54,099
January 26, 2014
Stadium Series
Yankee Stadium, New York, New York
New York Rangers
New Jersey Devils
7–3
50,105
January 29, 2014
Stadium Series
Yankee Stadium, New York, New York
New York Rangers
New York Islanders
2–1
50,027
March 1, 2014
Stadium Series
Soldier Field, Chicago, Illinois
Pittsburgh Penguins
Chicago Blackhawks
5–1
62,921
March 2, 2014
Heritage Classic
BC Place, Vancouver, British Columbia
Ottawa Senators
Vancouver Canucks
4–2
54,194
January 1, 2015
Winter Classic
Nationals Park, Washington, D.C.
Chicago Blackhawks
Washington Capitals
3–2
42,832
February 21, 2015
Stadium Series
Levi's Stadium, Santa Clara, California
Los Angeles Kings
San Jose Sharks
2–1
70,205
January 1, 2016
Winter Classic
Gillette Stadium, Foxborough, Massachusetts
Montreal Canadiens
Boston Bruins
5–1
67,246
February 21, 2016
Stadium Series
TCF Bank Stadium, Minneapolis, Minnesota
Chicago Blackhawks
Minnesota Wild
6–1
50,426
February 27, 2016
Stadium Series
Coors Field, Denver, Colorado
Detroit Red Wings
Colorado Avalanche
5–3
50,095
October 23, 2016
Heritage Classic
Investors Group Field, Winnipeg, Manitoba
Edmonton Oilers
Winnipeg Jets
3–0
33,240
January 1, 2017
Centennial Classic
BMO Field, Toronto, Ontario
Detroit Red Wings
Toronto Maple Leafs
5–4 (OT)
40,148
January 2, 2017
Winter Classic
Busch Stadium, St. Louis, Missouri
Chicago Blackhawks
St. Louis Blues
4–1
46,556
February 25, 2017
Stadium Series
Heinz Field, Pittsburgh, Pennsylvania
Philadelphia Flyers
Pittsburgh Penguins
4–2
67,318
December 16, 2017
NHL 100 Classic
TD Place Stadium, Ottawa, Ontario
Montreal Canadiens
Ottawa Senators
0–3
33,959
January 1, 2018
Winter Classic
Citi Field, New York, New York
New York Rangers
Buffalo Sabres
3–2 (OT)
41,821
March 3, 2018
Stadium Series
Navy–Marine Corps Memorial Stadium, Annapolis, Maryland
Toronto Maple Leafs
Washington Capitals
2–5
29,516
January 1, 2019
Winter Classic
Notre Dame Stadium, Notre Dame, Indiana
Boston Bruins
Chicago Blackhawks
4-2
76,126
February 23, 2019
Stadium Series
Lincoln Financial Field, Philadelphia, Pennsylvania
Pittsburgh Penguins
Philadelphia Flyers
4-3 (OT)
69,620
October 26, 2019
Heritage Classic
Mosaic Stadium, Regina, Saskatchewan
Calgary Flames
Winnipeg Jets
-
-
January 1, 2020
Winter Classic
Cotton Bowl Stadium, Dallas, Texas
Nashville Predators
Dallas Stars
-
-
February 15, 2020
Stadium Series
Falcon Stadium, Air Force Academy, Colorado
Los Angeles Kings
Colorado Avalanche
-
-

Question: what was the record  before Buffalo set the NHL record of 71,217 fans in the Winter Classic in 2008 ?
Answer: The 2003 Heritage Classic drew 57,167 fans, a league record that stood until 71,217 fans in Buffalo set another NHL record in the Winter Classic in 2008.