رَجَعَ الْمُسَافِرُ لَيْلًا، وَالطَّرِيقُ صَامِتٌ.
The traveller returned at night while the road was silent.
Wa-l-ṭarīqu ṣāmitun supplies the background condition concurrent with the return, and the circumstantial reading of wāw serves that function. A road is described by a quality associated with a silent person, giving the scene a light personifying image.
The general silence is set up before footsteps emerge. Identifying one personifying word without this sequencing misses the principal atmospheric effect.