Stuff to Do
The Grand Island Mansion is actually about 5-10 minutes from the town of Walnut Grove... and both are pretty remote... but check out the links below for some things you could do while you're in the area if you're feeling so inclined (we especially enjoyed the even littler town of Locke. the Grand Island Vineyards, and Giusti's)...
https://www.tripadvisor.com/Attractions-g33236-Activities-Walnut_Grove_California.html
https://www.airbnb.com/s/Walnut-Grove--CA/things-to-do
Click "Map" or "Satellite" views in the map below to see the location relationship with Grand Island Mansion.