That also depends where you are in the country, in Dundee they don't appear to have any that I can recall or very few while in Edinburgh they have a lot of lines painted on the road for cyclists - I hesitate to actually call them cycle lanes because 95% of the time there are cars parked in them which means if I'm meant to be in the cycle lane I've got to keep swerving round the cars or go the other way and mount the pavement. To keep swerving is almost certainly as unsafe as if I just sit about a car width away from the pavement regardless so I can maintain a steady speed and direction. While I'm on the subject it would be nice if cars wouldn't sit on the cycle 'boxes' in front of certain traffic lights, they are there for a reason.
Both cyclists and motorists do things to aggravate the other party, a little bit of courtesy goes a long way though.
Plenty of them in Dundee mate, although several are actually cycle paths as opposed to lanes. Doesn't stop the cyclists on the main road weaving all over the place though!
It has been quite a while since I've tried cycling around Dundee.