The Castle is a cinder block tower with 8" thick walls.  It measures 32" x 32" inside, stands 12' tall and is set on a 5' x 5' x 10" concrete slab.  The top opening is reduced to 16" x 16" and located on the north edge to reduce the amount of sunlight that enters the tower.  It was completed in 1994.
     These Chimney Swift babies pictured are in a Castle nest.  They are 3 to 6 days in age.

The Prism is a wooden tower with inside walls of Textured 1-11 siding with the grooves running horizontally.  It is a three-sided structure measuring 22" x 22" x 22" inside, 8' tall and stands on 2' tall pipe legs set in a 3'x 3' x 6" concrete slab.  The top opening is reduced to a triangular opening measuring 9" x 9" x 9" in the northwestern corner.  It has a ¾" airspace with a 1/8" hardboard skin and ½" rigid insulation covered by vinyl siding.  Construction of this tower was more difficult that a rectangular tower, but it has proved to be one of the most successful towers on the preserve.

The Fence Towers:   We are in the process of fencing the perimeter of the property encompassing the canyon.  Our hope is to install swift towers every 60 feet along the east and west sections which are bordered by pavement.  In 2003 we completed the fifth of these towers.  Each is set on a 3' x 3' x 6" steel-reinforced concrete slab.  They are constructed of 8" x 4" x 16" cinderblock.  The towers measure 20" x 20" outside and have an inside diameter of 12".  The towers stand 10 ½' tall.  To date only one of these towers has been occupied.