I would say the government, but not even that anymore, because nobody maintains them.

In Franco's regime, as they did not want to build the highways because they cost a lot of money and they knew something about economics, they decided to allow private companies to build and exploit them and save the government that money.

Little is said about this case in the world that breaks with the scheme that the government builds the highways.

Of course, during the Franco regime, taxes were hardly paid.