In reply to Northern Climber:
Stayed with friends in nearby Rankweil (Austria) a few years back. If you have bikes the Drei Lande (3 country) cycle route is well worth doing. It weaves through Austria, Switzerland & Liechtenstein, past medieval castles, the Rhine etc.....no passports shown either, as we were on minor roads the whole time.
A drive up to the Appenzell area (1.5hrs?)will get you to a stunning walk, with scrambling & via ferrata options, to the Santis observatory. This is on the stunning ridge that overlooks the Rhine valley. It's a long day but well worth the effort.
There's a couple of good via ferrata above Altach/Hohenems, near the Kapf peak.