USA

Newport News

1998-11-4

Australia　

Latrobe City

2000-3-7

ROK

Eumseong-gun

2000-9-27

Finland

Kotka

2001-9-19

Canada

Barrie

2006-6-8

Belgium

City of Huy

2007-08-03

New Zealand

Hutt County

2008-10-30

Italy

Pavia Province

2015-12-16