The lifting of the federal ban on the export of iron-ore in 1960 further boosted the economy. Rapidly increasing industrial and mining production fueled the rise of suburbanisation and consumerism in Perth and regional centres in the 1960s and 1970s. The Liberal governments of David Brand and Charles Court encouraged these developments. Foreign investment and the increase in the tax base was also used to modernise existing infrastructure. In the 1960s a metropolitan freeway system was constructed to link South Perth and Fremantle with the rapidly growing northern suburbs of Perth. Suburban shopping centres were built in Floreat, Morley, Forrestfield and Midland. A new container port facility was built in North Fremantle, Perth Airport was re-built and progressively the tram-trolley bus network was closed down.