Route 66 is an actual road, the number was given to it by the government so Steinbeck had no symbolic meaning for it in the book. Route 66 has an interesting and colorful history because it was one of the first major highways that spanned a good deal of the United States - though it was hardly a highway by comparison to the highways we have today. It was a two-lane road, not a wide multi-lane, separated stretch like we think of as a highway. In "Grapes of Wrath" and in reality, Route 66 represented hope and the possibility of a new beginning. Like the fictional Joads, many families drove to California on Route 66 in the hope of a better life in California during the Great Depression. The road stretched for over 2,000 miles, an unfathomable distance for most people. When the Joads set out on the highway, they hoped that the unseen end of their journey on it would give them jobs and a new life since their former world in Oklahoma had collapsed with the stock market and the drought. What they found along the way, though, were thousands of others going the in the same direction and hoping for the same outcome. They also found people who didn't want them there; people who were unfriendly to them like the gas station attendant who asks Tom if they plan to buy gasoline. They also come across a man who is on his way back to the midwest because he's been to California and has found that there is nothing there for them. The further along Route 66 the Joads travel, the worse things look for them. Grandpa, and then Grandma, dies. Noah leaves them. People are less and less friendly. The travel is foreshadowing for what is to greet them in California which is dirty squatter's camps, people who take advantage of them, discrimination, and starvation.