Picking the best in-state rivalry is easy. Alabama-Auburn. Picking the top 10 in-state rivalries is a little more difficult.
Lots of factors involved. Are they arch-rivals? Do they usually play at the end of the season? How many of their games have determined championships? How competitive has the series been? How competitive is the series now?
Here's our list, with one explanation. USC-UCLA and Stanford-Cal were not considered. They strike us as city rivals, not state rivals:
Series: Bama leads 41-34-1.
Name: Iron Bowl
History: The series was suspended in 1907 in a dispute over per diem for visiting teams and wasn't resumed until 1948.
Conference ramifications: Bama beat Auburn in defacto SEC title games in 1953, 1965, 1971 and 1979. The bitter foes met with division titles on the line in 1989 (Auburn), 1994 (Bama) and 2005 (Auburn).
National impact: 22 times both schools have finished a season ranked, including seven years when both were in the top 10 – 1963, 1972, 1974, 1986, 1989, 1994 and 2010.
Used to be…: Birmingham was the annual home for the Iron Bowl. Not until 1989 did Auburn host. The game was played in Tuscaloosa in 2000 for the first time in 99 years.
This year: No. 2-ranked Alabama, 10-1, hosts 3-8 Auburn on Saturday.
2. FLORIDA STATE-FLORIDA
Series: Florida leads 33-21-2
History: Didn't start until 1958 (FSU had been a girls school into the 1940s). Florida agreed to play by legislative threat.
Conference ramifications: Never in the same conference
National impact: Florida beat Florida State in 1996 national title. 20 times both teams have finished ranked in the polls, including eight times with both in the top 10.
Used to be…: The biggest game annually in college football. From 1993 through 1999, the schools combined for three national titles. Both finished in the top 10 every season from 1991 through 1998.
This year: Fourth-ranked Florida plays at No. 10 Florida State on Saturday in a battle of 10-1 teams.
3. CLEMSON-SOUTH CAROLINA
Series: Clemson leads 65-40-4
Name: Palmetto Bowl
History: From 1896-1959, the game was played on the state fairgrounds of Columbia, the home city of the Gamecocks.
It moved to the campuses in 1960.
Conference ramifications: The rivals shared a conference from 1922 through 1970 but played only once for the title. Clemson beat South Carolina in 1967 for the ACC crown.
National impact: Four times both finished ranked, but never both in the top 10.
Used to be…: When this game was played on the fairgrounds, it was played on a Thursday in October and referred to as Big Thursday. It moved to the season finale in 1962.
This year: 11th-ranked Clemson, 10-1, hosts No. 12 South Carolina, 9-2, on Saturday.
4. OKLAHOMA STATE-OKLAHOMA
Series: OU leads 82-17-7
Name: Bedlam Series
History: In the 1940s, OU tried to get the game moved permanently to Norman.
Conference ramifications: Weren't together in a league until 1960. OSU's win in 1976 helped forge a three-way tie for the Big Eight title with OU and Colorado. In 1984 and 2010, OU won games that decided the league or division title. OSU did the same in 2011.
National impact: Eight times both teams have finished ranked, with the 1984 shootout (No. 2 vs. No. 3) the highlight.
Used to be…: Incredibly one-sided. Between 1945 and 1995, OSU won three times.
This year: 13th-ranked OU (8-2) hosts No. 21 OSU (7-3) on Saturday with at least a share of the Big 12 title still possible for both.
5. MICHIGAN STATE-MICHIGAN
Series: Michigan leads 67-32-5
Name: Paul Bunyan Trophy
History: In 1973, Ohio State and Michigan tied for the Big Ten title. Conference athletic directors had to vote on which team to send to the Rose Bowl. Michigan State cast the deciding vote – and voted for the Buckeyes.
Conference ramifications: They never play for the Big Ten title, since their games always are in October or the first week of November, but three times the Wolverines and Spartans have finished 1-2 or 2-1 in the Big Ten, including ties for the title in 1978 and 1990.
National impact: 14 times both have finished ranked, including three times with both in the top 10 – 1950, 1956 and 1999.
Used to be…: Michigan State ruled the series. Under Biggie Munn and Duffy Daugherty the Spartans went 14-4-2 in the series from 1950-69.
This year: Michigan State, now 5-6, lost 12-10 at Michigan, now 8-3 and ranked 19th, back in October.
6. OREGON-OREGON STATE
Series: Oregon leads 59-46-10.
Name: Civil War
History: They play for the Platypus Trophy. Both schools had long stretches of ineptitude, but the Ducks' surge in the 1990s caused the Beavers to improve, too.
Conference ramifications: The schools have been together in a league since 1916 but only three times have met for conference supremacy. Oregon State won in 1957 to tie for the Pac-8 with Oregon, Oregon State won in 2000 to forge a three-way tie with Oregon and Washington, and Oregon won in 2009 to avoid a Pac-10 tie with the Beavers.
National impact: Only thrice have both teams finished ranked, with 2000 the highlight – Oregon No. 7, Oregon State No. 4.
Used to be…: One of America's worst games. From 1972 through 1993, 12 times both teams finished seventh or worse in the Pac-8/10.
This year: Fifth-ranked Oregon plays at No. 15 Oregon State on Saturday, with the Pac-12 North still up for grabs.
7. GEORGIA TECH-GEORGIA
Series: Georgia leads 62-39-5
Name: Clean, Old-Fashioned Hate
History: Tech's Bobby Dodd won 11 times in 15 years (1949-63), but Vince Dooley arrived in 1964 and put a stop to that.
Conference ramifications: Both charter members of the SEC (1933), but Tech left after 1963. Georgia beat Tech 42-0 for 1942 SEC title.
National impact: Nine times both have finished ranked in the polls, but only in 1942 and 1966 were both top-10.
Used to be…: One of the South's biggest games. The rise of Florida and Florida State have knocked Georgia Tech-Georgia down a bit.
This year: No. 3-ranked Georgia, 10-1, hosts 6-5 Georgia Tech on Saturday.
8. OLE MISS-MISSISSIPPI STATE
Series: Ole Miss leads 58-44-6
Name: Egg Bowl
History: The series was played in Jackson, the state capital, from 1973-90.
Conference ramifications: The Egg Bowlers have shared a conference since 1899 but have met only once for the title – Mississippi State won 6-0 in 1941 to win the SEC.
National impact: Five times both have finished ranked, though never both in the top 10.
Used to be…: Ole Miss coach Johnny Vaught was the king. In 25 games against the Bulldogs, 1947-73, he lost twice.
This year: Mississippi State, 8-3, plays at 5-6 Ole Miss on Saturday.
9. ARIZONA STATE-ARIZONA
Series: Arizona leads 47-37-1.
Name: Territorial Cup
History: ‘Zona dominated, winning 20 of the first 22 games, from 1899-1948. A 67-0 thrashing in 1946 prompted ASU officials to form the Sun Angel Foundation as a way to embolden the program.
Conference ramifications: From 1964-77, the schools won or shared eight of the 14 WAC titles. But then they jumped to the Pac-10 and have made little dent. ASU won the Pac-10 in 1986 and 1996; Arizona tied for the title in 1993 and ASU did the same in 2007.
National impact: Only twice have both finished ranked in the polls, 1975 and 1986.
Used to be…: Frank Kush owned the series. His Sun Devils went 13-1 from 1965-78.
This year: 7-4 Arizona hosts 6-5 Arizona State on Friday.
10. BRIGHAM YOUNG-UTAH
Series: Utah leads 52-31-4
Name: Holy War
History: The series began in 1922. Through 1957, there had been 33 meetings, and BYU had won just once.
Conference ramifications: The Utes and Cougars shared a conference from 1922-2010 but never played for the league title. They finished 1-2 (Utah ahead) four times between 1932 and 1957, then twice in the old WAC (BYU ahead) in the 1970s. They tied for titles in 1995 and 1999.
National impact: Three times both have finished ranked, but never both in the top 10.
Used to be…: BYU's Lavell Edwards owned the series. He arrived in 1972 and went 19-2 his first 21 games against Utah.
This year: Utah, now 4-7, won at home against BYU 24-21 on Sept. 15. The Cougars are 6-5.