The defensive squad of the Pittsburgh Steelers in the 1970s (the height of the Cold War, which probably had something to do with the origins of the nickname) was known as the Steel Curtain. Led by the front four of Dwight White #78, Ernie Holmes #63, Joe Green #75, and L.C. Greenwood #68, this defensive lineup was one of the best ever to take the field. The rest of the lineup (in 1974-75) consisted of linebackers Jack Ham (LLB), Jack Lambert (MLB), and Andy Russell (RLB); and secondary J.T. Thomas (LCB), Mel Blount (RCB), Mike Wagner (SS), and Glen Edwards (FS). It's often said that offense wins games, but defense wins championships. This defense led the Steelers to four Super Bowls in six years.

In the 1974 and 1975 seasons, only two times each season did the Steelers' opponents manage more than 17 points. In the 1974 playoffs, a powerful Oakland Raiders offense was held to 29 rushing yards; two weeks later, the Minnesota Vikings ran for a total of 17 yards in Super Bowl IX.

The 1976 season was one of the most exemplary for the steel curtain. In the last 8 games of the season, the Steelers defense had 5 shut outs and gave up only 22 points, 16 of which came in one game against the Houston Oilers. At one point, the defense had a streak of 22 consecutive quarters - 5 1/2 games - without giving up a touchdown.

Here's the 1976 Steelers record:


Despite its excellence, that 1976 team was not a Super Bowl winner. The Steelers lost the AFC Championship game to Oakland 24-7, after injuries put both their starting running backs (Franco Harris and Rocky Bleier) on the bench earlier in the playoffs.
Note: there is much more to add here, but much has already been said and I didn't want to make this node cut and paste. I'll add more details later, but this node will probably be a factual writeup for some time to come, since this team played before I was born and I really can't add to what has already been said about them. Read about the inspiration of Chuck Noll, the on-the-field leadership of Jack Ham and Jack Lambert, and heck, read about the Steelers offense: you'll hear about Terry Bradshaw, Franco Harris, Lynn Swann, Mike Webster, and if nothing else, the Immaculate Reception...this was a good decade for Pittsburgh. Just too bad I couldn't have been around to see it.