At the same time a major debate was also raging in Madrid about public transport. The city had a metro system dating back to 1919 but traffic congestion was choking the life out of the Spanish capital and it was clear something had to be done. Major investment in public transport was required. The authorities again went for metro in a big way. In the intervening eight years over 110 kilometres of new lines, 75 new stations, and new interchanges with suburban rail have been built. Almost 90% of the new network is underground.