What factor made New Mexico ideal for a top-secret lab and testing site?

New Mexico's sparse population and isolation created an environment conducive to establishing a top-secret lab and testing site. The region's low population density meant fewer people were nearby, reducing the risk of public exposure to potentially dangerous experiments or tests. Additionally, the isolation provided a level of security and confidentiality necessary for sensitive operations, allowing for the development and testing of technologies without interference or discovery.

Moreover, the vast and varied terrain of New Mexico offered a range of geographic features that were advantageous for certain kinds of testing, from desert landscapes to mountainous regions, which could accommodate various operational needs. The combination of these factors made New Mexico uniquely suited to host secretive governmental and military projects, such as those related to nuclear research during the Manhattan Project.