Posting a birdhouse in the backyard is a great way to attract feathered friends, but some of the greatest fun tends to remain hidden from view behind wooden walls.

This project by Nendo in Japan for a regional nature center provides small spaces for flying creatures but a larger viewing area for visitors as well.

One-way peepholes facilitate peaks into the nesting habits of the resident birds who enter smaller openings from the other side.

Aptly, the human entry side is shaped much like a traditional birdhouse but scaled up for people who can climb in via a ladder and circular opening.