The Vienna City hiking paths are signposted hiking trails managed by the Vienna Forestry Office (Municipal Department 49).
They are easily accessible by public transport, along the way there are restaurants, as well as picnic tables or children’s playgrounds.

Most of the city hiking trails are round trips, with a length of 7 to 15 kilometers and a walking time of about 2.5 to 5 hours. Most of these trails lead through the Vienna Woods.

Information about the individual routes can be found here:

https://www.wien.gv.at/english/leisure/hiking/paths.html

And detailed reports can be found here (german): http://www.bergnews.com/touren/stadtwanderwege-wien.php