My cottage is 30 min outside Oslo with a ferry. (20 min on the boat, and 10 min walk my house.)
If you want to have Norwegian nature experiance and at the same time be close to Oslo this is an ideal location.
This location is a perfect for a family. You can use our pier to go swimming in the fjord. There are good hikes around. Or a creative vacation. If you are working on your book, writing some music, developing a project, my house is fully charged with that vibe. That is what I do.