Complex sentence: Ferries services stopped around May 1965 after the highway and railway connections had been constructed making it easyer to transport the copper, but high operating costs and taxes eventually forced the mine to close on November 1,1974.
Split into simpler sentences: Ferries services stopped around May 1965 after the highway and railway connections had been constructed. The connections made it easyer to transport the copper, but high operating costs and taxes eventually forced the mine to close on November 1,1974.