At first glance, the nationwide map of Amtrak routes appears to be a sprawling spiderweb of interconnected rail lines doubling over one another as they crisscross the country. But to the trained eye, it’s a vast network of cycling opportunities. “Biking has been my main mode of transportation my whole life. I don’t own a car, so getting around by bikes and buses and trains is kind of just what I do,” says Emily Loberg, an Adventure Cycling tour leader who relies almost exclusively on ...