In a short, special one-off episode of "One Thing to do in L.A. this Week," we take you to the Most Important Spot in Modern L.A. History: Lang Station, in Canyon Country, which marks the spot where the Golden Spike connected Los Angeles to the Transcontinental Railroad in 1876! This moment was the day Los Angeles truly became a modern city. THIS is what you're going to do in L.A. this week.