Оригинальный текст - Японский - やっぱり箱根かな

This "Yappari, Hakone ka na?" is impossible to understand without the context.

One interpretation could be:
"You know, I think I'll go to Hakone after all",
but literally, it just says:
"Hakone after all."

It's perfectly-formed Japanese, but there's no verb to explain to decontextualized readers just what the speaker wants to do in Hakone, or is thinking about Hakone.