I like planetary trails, where the orbits of the planets (or other celestrial objects) are proportionally reduced and placed in the landscape.

For example, this image from a park in Halle (Germany) shows the inner solar system: https://dubisthalle.de/wp-content/uploads/2023/06/Planetenwe... -- but one has to walk 500 meters to reach Pluto.

The German Wikipedia has quite a long list of planetary trails: https://de.wikipedia.org/wiki/Planetenweg