The year 1896. That is when Crawley Town were founded. Makes them older than Chelsea, Portsmouth, Norwich, even Leeds.
They were Crawley FC back then - Town was added in 1958 - original members of the West Sussex Football League, which did not include Brighton because they would not come along for another five years, in 1901.
So, a serious, historic club, even if Crawley did not enter the Football League until 2011. By then they had enjoyed an FA Cup run that pitted them against Manchester United in the last 16, had won the Southern League and the Southern League Cup, and had been county champions on four occasions.