CYCLE ROUTES:   DESIRABILITY

1 =  Not suitable
2 =  Suitable if it is the only option
3 =  Normal facilities
4 =  Better than average
5 =  Very suitable and worthy of design criteria for cycling
 
Urban Dual Carriageway (e.g. London) Cyclist need a bit of speed but there is plenty of room and the roads are wide with traffic lights which are generally safer than junctions w/o lights, if irritating. Parked cars opening doors can be a nuisance.  3 Lanes tend to be narrow on dual carriageways so when there is free flowing traffic you can end up getting squeezed. These can be very good when the traffic is stationary as you can often 
overtake between the lanes. Also, if the left hand lane is used for parking other traffic will tend to avoid it.
Inter-urban Dual Carriageway (connecting towns) These roads can be extremely dangerous with lots of fast traffic. Accidents are always very serious. Eschewed by most cyclists because of the danger. Motorways in all but name.  1 Tend to have very fast moving traffic with lanes too narrow to overtake cyclists. Not nice. Also tend to have junctions with long left hand filters or enormous roundabouts.
Arterial Route Single Carriageway (Inter-urban) The absence of junctions is advantageous but when these roads are busy and if they are narrow with tricky chicanes on bends, they can be a bit dangerous.  3 Usually very good. Generally there is good visibility and plenty of lane width to permit safe overtaking within the lane. Junctions tend to be infrequent. Some of the older type A roads can be narrow and windy with long stretches of double white lines.
Arterial Route Single Carriageway (Urban) Just about every single hazard imaginable, including junctions, parked cars, chicanes, with the only saving grace is that less traffic than dual carriageways but the high traffic density combined with awful roads make the speeds slower and crashes less serious.  2
Winding Country Lane Excellent, if it was not spoiled for the frequent motorists who are not looking for cyclists. 4 Very much dependent on width and volume of traffic. Narrow country lanes (without centre markings) tend to be wonderful as the thought of oncoming traffic keeps vehicle speeds down. On the other hand where the road is just wide enough for a lane in each direction 
vehicles will often overtake in the most dangerous locations.
Urban Single Carriageway with junctions Junctions are the main problem with careless drivers and can be busy with very little room and hold-ups are frequent. 3 Depends on the nature of the junctions, the width of the road, the volume of traffic, whether parking is permitted.
Quiet Residential Street Suitable for cycling but increasing traffic is making some roads awkward. 4 Fine for a very short journey. If you want to cover any distance by linking quiet residential streets you will be involved in a lot of turning manouevres at junctions with more busy streets.
Residential Street with Speed Humps Not as good as roads without speed restrictions.Pedestrians are a greater hazard on these.  4 Better than one with pinch points
Quiet Cul de Sac or Home Zone with through route for cyclists Good but the cyclist has to reduce speed for pedestrians. 4 So long as you are not actually wanting to go anywhere.
Bus Lanes Little experience apart from lots of stopping for buses, pedestrians stepping out, and worse than mixed roads.
Addenda: buses can be extremely dangerous.
2 Pretty much ideal. Its like having a cycle lane that is actually wide enough and much less likely to be obstructed. They also tend to follow the most useful routes. Even part time bus lanes tend to be traffic free all day and there is plenty of space to pass parked cars.
Country Cycle Path or Towpath Excellent despite a few horses and errant dogs. Can be slow.
Addenda:the surface can deteriorate badly in wet winters or if official cars drive on the path, that even dedicated Sustrans paths may become impassable for two months in winter, except by mountain bikes. Rating is then reduced to 2
5 Fine if your not in a hurry to get anywhere, the weather is fine and there is daylight, you don't mind stopping every half mile for a gate or some other obstruction and getting splattered in mud. Good for a Sunday afternoon ride with the children.
Urban Cycle Path More dangerous than the adjoining roads with lots of junctions, people and dogs in the way.  2 Lethal.Apart from the blue signs - is there a difference from pavements?
Pavements in Urban Areas Daft place to cycle with all hazards, illegal, and slow.  1 Lethal
Pavements adjacent to Country Arterial (rare) or Inter-urban Routes These lightly used tarmaced routes can be useful for cyclists as an alternative to the more dangerous roads. 5 Fewer junctions or pedestrians, but tend to be very narrow and poorly surfaced and can have a habit of stopping suddenly without warning.
Town Centre Street (with shops) Pedestrians can be a perpetual hazard. 4