I'm looking at getting some single trip insurance for a week in Spain and it seems fairly typical that cover for mountain biking is included, albeit (not including downhill racing and extreme terrain).

Question is, what does an insurance company define as extreme terrain? I'm no freeride God, and won't be riding anything more severe than an average UK trail centre – anyone had an insurer refuse to pay with this get-out or am I just worrying about nothing?

i used dogtag-europ assistance

What does an insurance company define as extreme terrain?

Anything they like so as to avoid paying a claim

Another vote for Dogtag. They do various sports cover so you can pick how much you want to be covered for, up to and including downhill racing (but excluding the Mega).

We have annual cover and unfortunately had to claim in for a ski accident while in Whistler. They sorted physio in resort, paid for lost ski days and the claim process was very smooth.