Following the dramatic conclusion of the Championship at the weekend, we now know which sides will be joining us in League One next season.
The Robins finished up bottom of the pile in the second tier after a miserable season in which they only amassed 41 points and were nine games without a win as the curtain came down on the season.
The O's last took on City back in the 2006-07 season, our first in League 1, when we had two tight games in the league where we lost 2-1 away in September and drew 1-1 in January, whilst we were also defeated 3-1 in the Football League Trophy.
Our biggest victory the Robins came on Christmas Day in 1913 when we ran out 5-2 winners in the old Division Two.
Our biggest defeat came in a 6-0 demolition at Ashton Gate in 1947.
BRISTOL CITY WINS: 41
ORIENT WINS: 26
Just over a year ago Wolverhampton Wanderers were fighting for their lives in the Premier League, yet come August 3 they will be lining up in League 1.
After a disastrous season, Dean Saunders was sacked as manager this week after taking charge for just 20 games and leading the club to the unwanted slice of history of being the first English club to suffer the drop from the first to the third tier in successive seasons twice.
The O's have faced Wolves only 11 times since World War Two with the last time being in the old Division Four back in the 1987-88 season when we were twice on the wrong-end of a 2-0 scoreline.
Our biggest win and defeat came way back in the 1906-07 season when we 4-0 at home and then were thumped 6-1 in the space of five days in December.
WOLVES WINS: 22
ORIENT WINS: 17
The Posh are more familiar opponents in the recent era and were last our counterparts in the 2010-11 season when they were promoted through the play-offs to the Championship.
Despite finishing below them in the table, we took four points off the Cambridgeshire side that season as a 2-1 victory in late April followed a 2-2 draw at London Road in November.
Our biggest win was a memorable 4-1 win in the relegation season of 1994-95 whilst our biggest defeat was 3-0 - a result we suffered twice in the 1998-99 season.
PETERBOROUGH WINS: 9
ORIENT WINS: 11