There are many places with special Cosmos fields, so you can probably find something close to where you are.
This year I went to Washinomiya 鷲宮, in Saitmama 埼玉県, which is on the Tobu Isezaki Line 東部伊勢崎線, or also accessible from Higashi Washinomiya 東鷲宮 on the JR Utsunomiya line 宇都宮線. Washinomiya’s Cosmos Fureai Road コスモスふれあいロード follows a river for 12km, and is lined by over 8 million plants, so it’s makes quite a lovely Sunday afternoon stroll. They also hold a festival during the peak season (usually a weekend mid October) at the Washinomiya Town Office 鷲宮市役場.
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