 Complete the following phrase:  The clubs official history rated 195556 as their best season to date. The newly promoted club achieved their highest ever finishing position of sixth in the First Division, reached the 1956 FA Cup Final, and became the first English club side to participate in European competition when they played their opening game in the group stages of the Inter-Cities Fairs Cup. Their only major trophy is the League Cup, which they won in 1963 and 