King's Cross was built as the London hub of the Great Northern Railway and terminus of the East Coast main line. It took its name from the King's Cross area of London, named after a monument to King George IV that was demolished in 1845.
One day, Gordon, Duck, and a visiting engine were arguing about what the name of the big station at London was. Gordon thought it was King's Cross, while the other engine thought it was Euston. Duck thought it was Paddington since he said he used to work there.