+------+  train   +---------+  bike   +-----+
| Bonn | =======> | Berlin  | .-.-.-> | Ulm |
+------+          +---------+         +-----+
  |                 :
  |                 : bus
  |                 v
  |       car     +---------+
  +-------------> | Potsdam |
                  +---------+
