There are several places where the view is amazing, but the perfect spot from this photo was discovered long time ago by Mitsuhisa, the 19th head of the Shimazu family, when he established the Sengan-en garden, with the Sakurajima mountain used as shakkei "borrowed scenery".
EXIF info:
Nikon Df
Lens: 24-70mm F/2.8G
Focal Length: 35mm
Aperture: F/7.1
Shutter Speed: 1/2500s
ISO Sensitivity: ISO 800