Underrated: why Nagano surprised me

Nobody plans a wine trip to Japan, and I get it, but Nagano genuinely surprised me. Cool-climate whites, some serious Merlot and Koshu, and tasting rooms with a hospitality you won't find anywhere else.

It's not cheap to build a trip around alone, but if you're already visiting Japan, a day or two in the Kikyogahara area is easy from Tokyo and completely different from the usual circuit.

Has anyone else tasted outside the 'classic' countries and been caught off guard? Where?