The differences start with the way the streets are organized. In Eafahan, everything looks smaller. Many of the streets are narrow because they used to be alleys for walking. When buildings were torn down, city planners used the space to make room for cars, but there is still not very much room. Fortunately, the cars are usually smaller too, so they can fit in these smaller streets. In Houston, the streets are very wide. Sometimes they have six lanes. There are special lanes for turning left and right. Even the traffic lights are bigger because they have a lot of arrows. These arrows give deivers permission to make left turns.