Write or collect a series of fragments that contemplate an abstraction. (For example the idea of the soul, the self, the nature of time, the color green, the presence of the past, the idea of renewal.) Record them as discrete units of audio.
Find a site that is somehow well paired with the contemplation, whether through historical association or accessible quietude or any other line of connection. The site needn’t be an obviously contemplative place. You could write a walk for an outdoor subway platform that contemplates commute or migration. The same walk, deployed on a walk next to a river, might cast an entirely different tone on the contemplation. What about the same walk up and down the aisles of your local Target?
Arrange your audio, perhaps through the tools of geolocation*, so that a walk through a site will trigger them to play.
The walk is not about the site, but the site becomes the necessary occasion for engaging the contemplation in this way.
*You can do this using a free app like Echoes, or you could make a playlist and a map and have the walker manually play different tracks at different points within a site. See the Practical Geolocation post under audio clinic for more.