In reply to jessegeerts:
> Are they talking about something different from some nice bolted lines by the sea? Or is there some particular danger about climbing on sea cliffs that I'm unaware of?
You can't know without a specific enquiry to the company. Nobody on UKC is going to be able to answer the question either because it depends on what the underwriters of the insurance say, you need to speak to them. Personally I'd recommend that you start enquiries 3 months before your trip and work on the assumption you'll need 20 or 30 hours spread out over that 3 months to get a proper answers to your questions.
Even then, you'll just be looking at more questions. I mean, right off the bat, what's the difference between big wall and aid climbing? Sleeping on the wall for a night? What if you fix half way, rap to the ground, sleep there and then send the next day, is that still a big wall? What if you get benighted on a long trad climb, sleep on a ledge and then have to finish the next morning - are you now magically no longer insured? Is it not a big wall if you don't sleep during the night and simply sit still shivering?!
How far from the sea is classed as a "sea cliff"?
If a climb has a couple of bolts on it and needs trad gear, is it bolted climbing or trad climbing?
If an artificial wall is outdoors, is it outdoor climbing or gym climbing?
This all might sound farcical but you have to remember that you are dealing with an insurance company and when it comes to any claims, they will be looking for any reason, however farcical, to get out of having to pay out. You don't have to look too far to find tales online of insurance refusing to pay out for helicopters or medical treatment despite the person getting into trouble during _exactly_ the sport they got the insurance for because some slimeball at the insurance company finds a way to twist the fine print.
My 2 cents: First have a look at the Austrian Alpine Club, they have a basic policy and something augmented for very long trips I think, take a look at the fine print anyway. If that isn't for you then take the more expensive option above because in the event of any claim on a crag even close to the sea, they are guaranteedly going to refuse to pay out.