国境の長いトンネルを抜けると雪国であった。(4/29)

Excite翻訳： When the train came out of a long tunnel at the border, it was a snowy country.
＠nifty翻訳： When the train came out of a long tunnel at the border, it was a snowy country.
Babel Fish： When the tunnel where the border is long is passed through it was snow country.
Google翻訳： Snow Country was exiting the long tunnel on the border.
Yahoo!翻訳： When it passed through the long tunnel of the border, it was a snowy district.
OCN翻訳： When I went through the long tunnel in the border, it was Snow Country.
Windows Live Translator: It was snow country and at the border long tunnel.
Livedoor: It was a snowy country when escaped from the long tunnel of the border.

Summary:
This is a very famous sentence from "Snow Country" written by Yasunari Kawabata.
Excite and @nifty add "the train" as Subject though the original sentence does not have it.
It seems that they have registered this expression in their dictionaries.