Why is Hollywood walk of fame famous?

What are negative consequences of the Colorado river? Does California have a castle law? How many tunnels are under ground through the US? Why are police cars painted black and white? Does the New York Statue of Liberty and the France Statue face each other? What was dunlow castle defening from? Who built the last castle in Wales? What is a downstream switch? How did the Aral sea affect people? What are the cross streets for Times Square? What island did Italian immigrants cross? What allowed Greek culture to spread across the Mediterranean Sea and Black Sea? What is California named after? Where is the Billboard Museum in Bethany Oklahoma located? What Challenge encouraged nations to participate in land and forest conservation? Where is the Childrens Museum Elizabethtown in Elizabethtown Kentucky located? What is a river's flat wide area of land along the side of it? What is a deep serving dish called? What agent of erosion is responsible for the formation of the Grand Canyon? Why do rainforest's have layers?