Menlo Park. 1 Residential city (1990 pop. 28,040), San Mateo co., W Calif.; inc. 1874. Electronic equipment and aerospace products are manufactured in the city. Menlo College and the SLAC National Accelerator Laboratory are there. 2 Uninc. residential community, Middlesex co., central N.J., in Edison township. It is the site of Edison Memorial Tower and state park, where Thomas Edison kept his laboratories (1876–1887). Buildings associated with the laboratories were moved to or replicated at Greenfield Village Museum at Dearborn, Mich. Menlo Park developed into a suburban community after the end of World War II.