Searching the archives for info on Japanese tripoints in preparation for my upcoming visit to Japan in November and possible attempts on some of these I found this message:

http://groups.yahoo.com/group/BoundaryPoint/message/17423

Which led me to

Despite the best efforts of babelfish I was not able to completely understand this page completely so I asked one of my Japanese friends for help. I thought his answer might be of interest to the group

From: Masatomo Goto
Sent: Friday, September 23, 2005 9:27 AM
To: 'Hugh Wallis'
Subject: RE: Japanese help

Hugh-san,

Yes,

"Mikuni"'s "mi" means three, "kuni" means country.

in Japanese,

三 ... three

国 ... country

So as you understands, "Mikuni" means "three countries".

This list of city/town with "mikuni" in name has created that

there were actual places which three "Han/prefecture(now)"

meet in one place in "Edo" era.

The second column explains the city/town is still the place

which three prefectures meet in one place.

◎ ... This mark's city/town is the place which three prefectures meets.

○ ... This mark's city/town is the place which TWO prefectures meets

●, × ... these cities are not the places which prefectures meets. i.e. in the prefecture.

"Edo" era is the last era which Shogun(Head of Samurai) was the

leader of the country. From after "Edo"era, that is "Meiji", this

country changed then emperor was the leader

of the country. Currently as you know, emperor is just a symbol

and have no power.

-Masatomo Goto