Edit: If anyone is interested I can write up the hunt. Got some good photos. It was this or a visit to https://en.wikipedia.org/wiki/Ytterby and I think the solar system was the best choice. They should really promote these attractions more.
I've also submitted it to HN: https://news.ycombinator.com/item?id=8181696
The system is at scale 1:680 000 000. Earth's model is about 1.9 cm in size and at 225 m distance from the sun's model, while Pluto's model is 7.7 km away from it...
"Uranus (2.6 m in diameter) was vandalized"
Sorry -- had to share that. Got it from the wonderful "Great Courses" intro to astronomy series (See? I managed to throw in some good hacker stuff and tell a corny joke at the same time.) Highly recommended.
SkyRide do free regular guided public rides down the route (or sometimes a subset there of for people who don't feel up to the full length and back) which is a pleasant way to spend an hour or two if you are in the area.
Other planets further away give you larger rings to search in; you could place Jupiter in a ring ~4 km wide ~39 km away, and it would be within the range of its orbit around the Sun.
That said, while the task is easier than you might think (since there isn't One True Position for each planet), I don't know how well they did.
> the model is a mat with a picture of Saturn, but will eventually grow to crown a school planetarium at the city
It'd be even better if there was an international solar system which involved several countries, to make it an even larger scale.
not to scale :)
Our local (Boise, ID) Discovery Center has a model, too. Fun stuff!