The sign says

Danger!

The sign says "Danger - High Voltage Electricity. Do Not Enter Without Permission (危高壓險電 未經許可嚴禁進入)" - Some kind of high powered generator/electric furnace?
Credit
Toby Johnston
Taken
03/09/2017
Camera
Nikon D7100
ISO
160
Shutter
1200 second
Aperture
ƒ/6.3
Focal Length
48mm
Lens
Nikon AF-S DX NIKKOR 16-85mm f/3.5-5.6G ED VR
License
Copyrighted
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Jinshan Ironworks 台灣煉鐵金山廠