Although it starts considerably south of the top of the island, at the ferry port of Beppu down the coast, in terms of distance this route is more or less the equivalent of crossing the entire island vertically from top to bottom. You can actually do this if you like; the ferry ports of Moji and Shin-Moj are located at the top of the island. However, Beppu was chosen as the starting point both because it's a major ferry terminus and because it’s where the road to the Yamanami Highway begins. You head right up into the mountains right out of the starting gate, but the climb up isn't nearly as difficult as you might expect (or as I expected after driving along it). Originally I had planned to go due south all the way through the interior. However, I was dissuaded by everyone I talked to -- they said that the section between Aso and Ebino was a sucession of steep climbs (one very experienced cyclist had confessed to almost bursting into tears at the summit of the steepest pass) without much scenery to compensate. Since there also appeared to be no places to stay on the stretch I was considering, and as I was carrying no camping gear, I decided to play it safe and head back to the coast and shoot straight down to Miyazaki. This is a very long haul (along a busy highway), but there is s lot of nice coastal scenery to compensate.

Note: if you have a limited amount of time and like pretty coastlines, you should know that the coastline SOUTH of Miyazaki (the famous Nichinan Kaigan) is much nicer than this section, and you might consider taking the train as far as Miyazaki and going down the coast from there. That coast will be covered in detail on this site in the future.