The boat hull has small center ridges that keep it standing upright. It's also designed not to topple over when rocked.

File information
Filename:	ir081-20190503-2403.jpg
Album name:	philbert / Hitachi-Otsu Ofune Matsuri Boat Festival 常陸大津の御船祭
Keywords:	ibaraki / kitaibaraki / ofune / matsuri / boat / festival
Filesize:	34 KiB
Date added:	Jun 03, 2019
Dimensions:	600 x 400 pixels
Displayed:	32 times
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