Developers of the Mountain View Commercial Center, a project site at a quarry formerly owned by Holliday Rock Company, are working with the cities of Upland and Claremont to create a vision for the site at the southeast corner of Base Line Road and Monte Vista Avenue, and will host a 6 to 8 p.m. interactive open house and forum Wednesday, January 31 at the Alexander Hughes Community Center, 1700 Danbury Rd., Claremont.