of winning the County Club Championship at senior, junior or intermediate levels (for adults) or under-21, minor or under-age levels (for children). A club may field more than one team, for example a club may field a team at senior level and a "seconds" team at junior or intermediate level. This format is laid out in the table below: Clubs may come together in districts for the County Championship or compete on their own. Though the island of Ireland was partitioned between two states by the British parliament in 1920, the organisation of Gaelic games (like that of most cultural organisations and religions) continues on an All-Ireland basis. At the national level, Ireland's Gaelic games are organised in 32 GAA counties, most of which are identical in name and extent to the 32 administrative counties on which local government throughout the island was based until the late 20th century. The term "county" is also used for some overseas GAA places, such as London and New York. Clubs are also located throughout the world, in other parts of the United States, in Great Britain, in Canada, in Asia, in Australasia and in continental Europe. The level at which county teams compete against each other is referred to as inter-county (i.e. similar to international). A county panel—a team of 15 players, plus a similar number of substitutes—is formed from the best players playing at club level in each county. The most prestigious inter-county competition in Gaelic football is the All-Ireland Championship. The highest level national championship is called the All-Ireland Senior Football Championship. Nearly all counties contest this tournament on an annual basis, with crowds of people thronging venues the length and breadth of Ireland—the most famous of these stadiums being Croke Park—to support their local county team, a team comprising players selected from the clubs in that county. These modified knock-out games start as provincial championships contested by counties against other counties in their respective province, the four Irish provinces of Ulster, Munster, Leinster and Connacht. The four victors in these then progress automatically to the All-Ireland series. In the past, the team winning each provincial championship would play one of the others, at a stage known as the All-Ireland semi-finals, with the winning team from each game playing each other in the famed All-Ireland Final to determine the outright winner. A recent (1990s/2000s) re-organisation created a "back door" method of