ATHENS — A little geography: The mainland of the United States is comprised of an area that combines for just more than 3.1 million square miles. There is football played throughout this area, from Seattle to Miami, which are more than 3,000 miles apart.

And yet when the four best teams were chosen for the College Football Playoff this year, it included three schools located within a few hours’ drive of each other:

• Georgia and Clemson, which potentially could meet in the championship game, are all of 72 miles apart.
• Alabama and Clemson, which will meet in the Sugar Bowl, are 325 miles apart.
• Georgia and Alabama, both members of the SEC, are 275 miles apart.

“It just goes to show that down South we’re all about football,” Georgia receiver Terry Godwin said. “We’re the hard-nosed team that’s going to grind at you, try to outmuscle you.”

Throw in Oklahoma, which meets Georgia in the Rose Bowl, and the four playoff teams are all in the geographic lower half of the country. Athens and Norman, Okla., for those interested, are 925 miles apart, which isn’t close — but still close enough that the staffs of the two teams have visited with each other to exchange notes. Georgia coach Kirby Smart and Oklahoma coach Lincoln Riley ran into each other earlier this month when they were recruiting the same high school in Georgia.

Still, there isn’t much overlap between Oklahoma and the other three — but there is plenty within the three.

The coaches practically all know each other. Smart was the defensive coordinator at Alabama for nine years before coming home to Georgia two years ago. Clemson coach Dabo Swinney is a graduate of Alabama.

The assistant coaches pass each other on the trail all the time, all three programs recruiting the same general, and plentiful, area in the Deep South. And many players know each other.

Godwin said he knows a lot of players at Clemson and Alabama, including Ray-Ray McCloud at Clemson and Mack Wilson and Calvin Ridley at Alabama. He said they haven’t spoken since the College Football Playoff brackets were announced (Clemson meets Alabama in the Sugar Bowl).

“It shows the North that this is how football is really supposed to be,” Godwin said.

So is one region’s dominance of the playoff a good thing? There’s evidence that it’s not.

The highest-rated championship game of the young playoff era was the first one, when it featured two teams from different regions: Ohio State and Oregon. Many more people watched that game than the two subsequent championship games, both matching Alabama and Clemson.

Ohio State and Oregon drew 33.4 million, and the following year Alabama’s 45-40 win over Clemson saw a 23 percent drop. And the rating for the Alabama-Clemson rematch last season saw another drop, although a slighter one.

During the BCS era, one of the lowest-rated championship games came when Alabama and LSU, two SEC teams, met in 2011. That game drew 24.2 million, according to The New York Times.

The highest-rated championship game of the BCS era — Texas beating Southern Cal in the 2005 Orange Bowl — was watched by 35.6 million. The next-highest rated was Ohio State and Miami in 2003, drawing 29.1 million.

It was Ohio State, of course, that was left out of the field this year in place of Alabama. Thus this was the first time in the four years of the playoff that one conference has two teams in it.

And a third, many would say of Clemson, is an SEC team in all but name.

Georgia safety J.R. Reed actually grew up closer to the other team, having been born and raised in Texas. Then he played one year of college ball at Tulsa before transferring to Georgia.

He was asked what he thought of this Deep Southern domination of the playoff.

“I think it’s just one of those years where the three teams just happen to be here,” Reed said. “It’ll be something if it just keeps happening over and over. But I just think it’s one of those things this year.”