The Twin Areas analysis is a tool used in site selection applications to compare the characteristics of target locations with an existing site, such as a top-performing store. This approach involves three main steps: selecting relevant variables, gridifying and enriching the location of the origin and target sites, and deriving a similarity score between the origin and each target location. The analysis can be run in Google BigQuery using CARTO's Analytics Toolbox, which provides a set of User Defined Functions and procedures for running advanced spatial analytics natively in BigQuery. By applying this approach, retailers and CPG brands can easily discover the best locations to expand or optimize their network without prior knowledge of the area, optimizing their site planning process.