Starting January 6th, the BBBase train will depart Ryogoku station every Saturday and Sunday morning. From January through March, each weekend of the month will focus on a different region of the Boso peninsula. Those interested in riding the BBBase must reserve their seat(s) at least 5 days in advance to one of the four courses: Sawara, Choushi, Uchibo, and Sotobo.
For each destination, JR East has meticulously prepared and made available online cycling route maps in short (avg. 20KM), middle (avg. 40KM), and long course (avg. 60KM) variations. Of course, more avid and exploratory cyclists may opt to seek more mileage (just be back to the appropriate train station in time for the return trip!).