In summer season, the busiest period is mid August. This period is called “Obon (お盆)”. Everybody try to go back to hometown in this period. In this year 2012, August 10 to 19 will be Obon period. Especially the direction to go out from major cities on Aug 10-12 and the direction to go into major cities on Aug 17-19 will be much busier. These dates are weekend days. Everybody will try to move on these dates. If you travel in this period, try to go opposite direction. It makes you to travel much easier.
Umisachi-Yamasachi (海幸山幸) is limited express train that is operated between Miyazaki (宮崎) and Nango (南郷). This train is named from Yamasachihiko (山幸彦) and Umisachihiko (海幸彦) in Japanese mythology.
This is not a real express train and is a kind of cruising train for sightseeing along Nichinan line (日南線). This train is suitable for the tourists who go to Aoshima (青島) and Udo Jingu shrine (鵜戸神宮) at Nichinan coastline (日南海岸). This train makes your trip more memorable.