Originally made of wood, the bridge was built in 1626, when the castle was rebuilt by the Tokugawa Shogunate with deeper moats and walls twice as tall as the original Toyotomi Hideyoshi construction.
But the bridge burned with the castle in 1868, during the Boshin war. The bridge we see today was rebuilt from concrete in 1965, after the castle was declared one of the "Special Historic Sites".
EXIF info:
Nikon D90
Lens: 18-70mm F/3.5-4.5G
Focal Length: 40mm
Aperture: F/5.6
Shutter Speed: 1/320s
ISO Sensitivity: ISO 400