According to this article:

Kuriyama Village's famous winter sightseeing destination, the "Brightly Shining Ice Lantern and Kamakura Festival" began on the 27th at Yunishigawa Onsen ...

... and will run until the end of February.

That's not "Kamakura" as in the city, it's "kamakura" as in "little playhouse made of snow". You can see some pictures of what I'm talking about here (scroll down to the second batch). Elementary and junior high school kids make a bunch of three-meter high snow forts, and the city illuminates them at night for the tourists.

Where does the word "kamakura" come from? Koujien has no kanji listed for it, and since they're originally an Akita thing from up north I don't think they have anything to do with Kamakura the city. Still, the kanji for Kamakura -- 鎌倉 -- mean "Sickle Storehouse", so maybe way back in the day people in Akita kept their sickles in snow houses during the winter. Seems like they'd rust, though.

Or maybe the "kama" comes from kami, "god", because, again according to the book of K, kamakura were originally used as part of a ritual/festival for the water god/s.