We failed to get to Iona and Lewis (I particularly wanted to see the stones at Callanish) because storms made it unsafe for the ferries. North West Scotland is the closest thing the UK has to a wild frontier, and transport can be vulnerable to the often unpredictable weather, as well as mechanical failure (the region is completely ignored by Westminster, and Holyrood aren't much better). That's why I dislike the modern requirement to pre-book everything. You really need to be able to react to the conditions and change plans as the situation changes.