The inter-island rail ferry service began in August 1962 by the New Zealand Railways Department (NZR). The service primarily provided a RORO rail link between its North and South Island networks, allowing NZR to compete directly with coastal shipping companies for inter-island freight. It also provided the first RORO road link between the two islands, which saw the Wellington to Picton ferries compete with, and then completely replace, the Union Company's Wellington–Lyttelton ferry service. Today, the Interislander service is still well patronised despite competition on the Wellington–Picton sea route with Bluebridge and from airlines, carrying around one million passengers and 230,000 vehicles per year on 5,500 sailings.