Of the rest of the land, 20.7% is settled (buildings or roads) and the remainder (2.1%) is non-productive (rivers or lakes).

[3] Since 2008 Fahr Monastery forms a small exclave of the municipality, otherwise surrounded by Unterengstringen of canton Zürich.

The blazon of the municipal coat of arms is Per fess Argent and Gules a Key in pale counterchanged.

[3] The age distribution, as of 2008[update], in Würenlos is; 548 children or 10.4% of the population are between 0 and 9 years old and 627 teenagers or 11.9% are between 10 and 19.

[8] The historical population is given in the following table:[7] The Benedictine women's convent of Fahr in Würenlos was founded around 1130 AD.

It is listed as a heritage site of national significance, as is the Ancient Roman quarry in Würenlos.

[3] From the 2000 census[update], 2,136 or 44.6% are Roman Catholic, while 1,750 or 36.5% belonged to the Swiss Reformed Church.