One of the five main demands used to measure the quality of cycling infrastructure (the others are cohesionsafetydirectness, and comfort).

This refers both to the attractiveness of the environment, and to social safety. Cycle routes should be routed through areas of high public safety; well-maintained, and well-lit, and insulated from noise.

Attractiveness and social safety, Zwolle

From 'Cycle Traffic and the Strategic Road Network' - 

Aesthetics, noise reduction and integration with surrounding areas are important.