Since 1884 the site has been used primarily by the GAA to host Gaelic games, most notably the annual finals of the All-Ireland Senior Football Championship and Senior Hurling Championship. Music concerts by major international acts have also been held in "Croker", as it is often called, and it hosted the opening and closing ceremonies of the 2003 Special Olympics. During the refurbishment of Lansdowne Road the stadium is also hosting the Irish national rugby union and soccer teams.
Following a redevelopment programme started in the 1990s, Croke Park has a capacity of 82,300, making it the fifth largest stadium in Europe and the current largest stadium in the Six Nations Championship.
During the Irish War of Independence on November 21, 1920 Croke Park was the scene of a massacre by the Auxiliary Division. British army auxiliaries – nicknamed the Auxies but often referred to by the nickname of another Royal Irish Constabulary (RIC) paramilitary force, the Black and Tans – entered the ground, shooting indiscriminately into the crowd killing 14 during a Dublin-Tipperary gaelic football match. The dead included 13 spectators and Tipperary's captain, Michael Hogan. Posthumously the Hogan stand built in 1924 was named in his honor. These shootings, on the day which became known as Bloody Sunday, were a reprisal for the assassination of 14 British Intelligence officers, known as the Cairo Gang, by Michael Collins's 'squad' earlier that day.
In the 1920s the GAA set out to create a high capacity stadium at Croke Park. Following the Hogan Stand, the Cusack Stand, named after Michael Cusack from Clare (who founded the GAA and served as its first secretary), was built in 1927. 1936 saw the first double-deck Cusack Stand open with 5,000 seats, and concrete terracing being constructed on Hill 16. In 1952 the Nally Stand was built in memorial of Paddy Nally, another of the GAA founders. Seven years later, to celebrate the 75th anniversary of the GAA, the first cantilevered "New Hogan Stand" was opened.
The highest attendance ever recorded at an All-Ireland Senior Football Final was 90,556 at the 1961 Offaly v Down final. Following the introduction of seating to the Cusack stand in 1966, the largest crowd recorded since has been reduced to 82,516.
In the 1980s the organisation decided to investigate ways to increase the capacity of the old stadium. The design for an 80,000 capacity stadium was completed in 1991. Gaelic Sports have special requirements as they take place on a large field. A specific requirement was to ensure the spectators were not too far from the field of play. This resulted in the three-tier design from which viewing games is possible: the main concourse, a premium level incorporating hospitality facilities and finally an upper concourse. The premium level contains restaurants, bars and conference areas. The project was split into four phases over a 14-year period.
Although the stadium has completed all four phases, there is speculation that future development will include a roof for the stadium. The Hill 16 end is unlikely to be developed further in the near future with a second upper tier (in line with the other 3 sides) due to the proximity of the railway line and the fact that there are houses immediately behind the raised wall on which the rail line runs meaning the GAA would have to buy a street of houses to expand Hill 16 to anything more than a terrace.
The pitch in Croke Park is a Desso GrassMaster pitch which was laid in 2002 replacing the existing grass pitch. This is a modern development in pitch design which couples natural grass with a stitching of synthethic fibres. The close proximity of the stitching and the natural grass roots growing around the stitching is what gives the pitch its stability and is the key to the success of this type of surface. The system is employed in sports venues in Holland, England and the US.
Since January 2006, a special growth and lighting system called the SGL Concept has been used to assist grass growing conditions, even in the winter months. The system, created by Dutch company SGL (Stadium Grow Lighting), helps in controlling and managing all pitch growth factors, such as light, temperature, CO2, water, air and nutrients.
With the 2007 Six Nations clash with France and possibly other matches in subsequent years requiring lighting the GAA installed floodlights in the stadium (after getting planning permission). Indeed many other GAA grounds around the country have started to erect floodlights as the organisation starts to hold games in the evenings, whereas traditionally major matches were played almost exclusively on Sunday afternoons. The first game to be played under these lights at Croke Park was a National Football League Division One match between Dublin and Tyrone on 3 February 2007 with Tyrone winning in front of a capacity crowd of over 81,000 - which remains a record attendance for a National League game. with Ireland's Six Nations match with France following on 11 February. Temporary floodlights were installed for the American Bowl game between the Chicago Bears and the Pittsburgh Steelers on the pitch during the 1990s, and again for the 2003 Special Olympics.
Up until the early 1970s, rule 27 of the GAA constitution stated that a member of the GAA could be banned from playing its games if found to be also playing soccer, rugby or cricket. That rule was abolished but rule 42 still prohibited the use of GAA property for games with interests in conflict with the interests of the GAA. The belief was that rugby and soccer were in competition with football and hurling, and that if the GAA allowed these sports to use their ground it may be harmful to Gaelic games, while other sports, not seen as direct competitors with gaelic football and hurling, were permitted, such as the two games of American football (one college game between Notre Dame and Navy, and an American Bowl NFL preseason game between the Chicago Bears and the Pittsburgh Steelers) on the Croke Park pitch during the 1990s.
On 16 April 2005, a motion to temporarily relax rule #42 was passed at the GAA Annual Congress. The motion gives the GAA Central Council the power to authorise the renting or leasing of Croke Park for events other than those controlled by the Association, during a period when Lansdowne Road – the venue for international soccer and rugby matches – is closed for redevelopment. The final result was 227 in favour of the motion to 97 against, 11 votes more than the required two-thirds majority.
In January 2006, it was announced that the GAA had reached agreement with the FAI and IRFU to stage two Six Nations games and four soccer internationals at Croke Park in 2007 and in February 2007, use of the pitch by the FAI and the IRFU in 2008 was also agreed. These agreements were within the temporary relaxation terms, as Lansdowne Road will still be under redevelopment until early 2009. Although the GAA said that hosted use of Croke Park would not extend beyond 2008, irrespective of the redevelopment progress , the official fixture list for the 2009 Six Nations rugby tournament anticipates the Irish rugby team using Croke park for a third season. 11 February 2007 saw the first Rugby Union international to be played there. Ireland were leading France in a Six Nations clash, but lost 17-20 after conceding a last minute (converted) try.
A second match between Ireland and England on 24 February 2007 was politically symbolic because of the events of Bloody Sunday in 1920. . There was considerable concern as to what reaction there would be to the singing of the British National Anthem God Save the Queen. Ultimately the anthem was sung without interruption or incident, and applauded by both sets of supporters at the match, which Ireland won by 43-13 (their largest ever win over England in rugby).
On the 24 March 2007 the first soccer match took place at Croke Park. The Republic of Ireland took on Wales in a Euro 2008 Qualifier, in which a Stephen Ireland goal secured a 1-0 win for the Irish in front of a crowd of 72,500. Prior to this, the IFA Cup had been played at the then Jones' Road in 1901, but this was 12 years before the GAA took ownership.