These not-so-behind-the-scenes unsightly structures do spoil the otherwise spectacular scenery, and in trying to find out their purpose, it seems that the dam is called the Ogochi Dam, completed in 1957 after 30 years planning (including stall time during 2nd WW), and is a control for the flow of the Tama River, which is a major water supply source to central Tokyo.
The other factory found just outside JR Okutama Station Terminal is a limestone excavation factory, being one of the major economic production of this town (others include agricultural products such as wasabi roots, and shiitake mushrooms).
Actually, beyond the JR terminal, this company operates an old freight tram line (Mizune Line) which runs in and out of tunnels for a distance, and is not accessible to the public.
Updated Feb 1, 2008
Fortunately it's just a literal translation of "tourist toilets", as in public toilets for use by tourists, though the word choice in the original Japanese is rather dodgy too.
Updated Feb 2, 2008
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Fortunately it's just a literal translation of "tourist toilets", as in public toilets for use by tourists, though the word choice in the original Japanese is...
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