Though automobiles were invented prior to the 20th century, mass production of vehicles in the early 20th made them widely available; thus, they became a symbol of modernity. The two small axes around the Monumental axis provide loops and exits for cars to enter small roads. Some argue that his emphasis of the plan on automobiles caused the lengthening of distances between centers and it attended only the necessities of a small segment of the population who owned cars. But one can not ignore the bus transportation system in the city. The buses routes inside the city operate heavily on W3 and L2. Almost anywhere, including satellite cities, can be reached just by taking the bus and most of the Plano Piloto can be reached without transferring to other buses.