Will Drexler submitted this bike/run/bike challenge, which is the brain child of Lamar Felix of Pittsburgh, PA.  It is also known as the "Felix Classic":

The Waterloo-Pinckney Trail is a 36-mile-long hiking trail which runs through Waterloo State Recreation Area and Pinckney Recreation Area in southeastern Michigan, United

The Eifelsteig is 313 kilometres long in total and is divided into 15 daily stages of between 14 and 28 kilometres each. The first stage is the shortest by far, with just 14 kilometres. All the other stages are around 20 kilometres long. The most intensive way of experiencing the Eifelsteig hiking trail is to hike for several days in a row. Here, Eifel Tourismus GmbH and other hiking tour operators offer multiple day packages, which include baggage transportation, packed lunches and overnight stays in hotels.