Bluebirds only nest in existing cavities, like your birdhouse. Build your own bluebird house and attract gentle bluebirds. This is a great way to teach children about nature at an early age. Features 1-9/16 inch entry hole to discourage predators and protect your nesting bluebirds. Mount against any flat surface. Open the front panel for easy cleanout. Made from rugged Western cedar. Once assembled, the bluebird house measures 6-1/4 x 7 x 11-3/4 inches tall.