Question: Cambridge United Football Club is a professional association football club based in the city of Cambridge, Cambridgeshire, it currently plays in which level league, the fourth tier of the English league system, also known as the football pyramid, is a series of interconnected leagues for men's association football clubs in England, with six teams from Wales and one from Guernsey also competing.?

 The system has a hierarchical format with promotion and relegation between leagues at different levels, allowing even the smallest club the theoretical possibility of ultimately rising to the very top of the system, although in practice it would take a team at the bottom levels at least two decades of consistently finishing at or near the top of each successive league to reach the top level, and even then additional restrictions, particularly in regard to stadium facilities, would then come into effect at the highest levels that could prevent a club from being allowed access to the top levels.  There are more than 140 individual leagues, containing more than 480 divisions. The English football league system, also known as the football pyramid, is a series of interconnected leagues for men's association football clubs in England, with six teams from Wales and one from Guernsey also competing. <SEP> Cambridge United Football Club is a professional association football club based in the city of Cambridge, Cambridgeshire.  The club currently plays in League Two, the fourth tier of the English league system. <SEP> Cardiff City Football Club, a professional association football club based in Cardiff, Wales, was founded in 1899 as Riverside A.F.C. by members of Riverside Cricket Club.  The club's first year was made up of friendlies before they were admitted to the Cardiff & District League in 1900 and later the South Wales Amateur League in 1907.  The following year, the club were granted permission to adopt the name Cardiff City, having been denied the previous year as they were deemed not to be playing at a high enough level, and moved into the English football league system for the first time by joining Division Two of the Southern Football League.  They won promotion to Division One in the 1912–13 season and remained there until 1920, playing just three seasons during this time due to the outbreak of the First World War when league football was abandoned.  In 1920, they were elected to The Football League, joining the Second Division for one season, winning promotion in their first season after finishing second.  The club also competed regularly in the Welsh Cup, winning the trophy 22 times during their history, second only to Wrexham's 23, before they were denied entrance into the competition from 1995 onward by the Football Association of Wales, along with all other clubs playing in the English league pyramid. <SEP> Colchester United Football Club is an English professional football club based in Colchester, Essex, that was founded in 1937.  The club went on to compete in the Southern Football League from 1937 until 1950, when they were elected to the Football League.  During this time, Colchester produced one of the most notable FA Cup runs by a non-league side in 1947–48, as they defeated fellow non-leaguers Banbury Spencer in the first round, before beating Football League clubs Wrexham, Huddersfield Town and Bradford Park Avenue.  They finally fell to Blackpool in the fifth round.  The club played in the Third Division South for eight seasons, until the league was re-organised at the end of the 1957–58 season.  The club finished in 12th position in the table, meaning that from the 1958–59 season, the U's would be playing in the Third Division.  Colchester remained in the Third Division until they were relegated in 1961, but made an immediate return to the third tier when they finished the 1961–62 season in second position, one point behind champions Millwall.  Three years later, the club finished 23rd of 24 clubs in the Third Division, as they were relegated back to the Fourth Division.  Another single season in the fourth tier followed as Colchester were promoted in fourth position.  Their spell in the Third Division didn't last long, as they again finished in the relegation zone in 1968.  The U's remained in the Fourth Division for a further six seasons, but during this period, the U's embarked on one of the most notable runs in FA Cup history, as manager Dick Graham took his ageing side to the 1970–71 quarter-finals.  They dispatched non-league side Ringmer, before knocking-out Cambridge United, Barnet and Rochdale following a replay.  United faced Don Revie's Leeds United in the fifth round, who were at the top of the First Division at the time.  The U's race to an unprecedented 3–0 lead in the match, before Leeds pulled two goals back.  The match ended 3–2 to Colchester to record a famous giant-killing victory.  They then faced Everton in the quarter-final match but lost 5–0 at Goodison Park.  Three seasons later, Colchester sealed promotion once again as they ended the 1973–74 season in third place.  Relegation followed in 1976, with promotion following one season later.  Colchester returned to the Fourth Division for the final time in 1981 as they finished 22nd of 24 teams.  The club struggled financially in the late 1980s and suffered a drop in form, causing them to finish bottom of the Football League in 1990 and were relegated to the Conference.