Being from the UK, I'm familiar with the pavement (sidewalk) bike facilities to which Raleigh Chopper refers. I do not like them as they blur the distinction between roadway and pedestrian space. Moreover, many pedestrians forget that there is a right of way for bikes, despite markings and signs. They also invite trouble at side road junctions. The cyclist technically has right of way, in some cases - but you'd be foolish to chance it.
Really, they are a cop out by councils who can then say "We created XYZ miles of safe cycling routes in this county" I see kids and some slower cyclists on these paths very infreqently. They are unusable at even moderate speeds. Most opt for the road instead - you know where you stand there. In a few places in Oxford there are pavements marked with bike paths AND bike lanes marked on the road... Not what I'd term joined-up thinking... and thoroughly inconsistent where they are implemented.
Ed
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Get a bicycle. You will certainly not regret it, if you live.