The observatory is an open shelter built with basaltic andesite lava found at the construction site. The viewing windows are cut to specifically highlight the neighboring mountains. These lava tube viewing holes allow visitors to easily identify the different Cascade peaks. There is also a 36 inch (90 cm) diameter, bronze azimuth-like peak finder on the observatory's roof to help visitors locate nearby geologic features as well as the surrounding mountain peaks. From the top of the observatory, visitors have a panoramic view of the Cascade Mountain Range including Mount Hood in the far north.