The Barangay Post Proper Southside, located in District II, hosts several historical and tourist sites namely: Philippine Army Museum and American Cemetery. By clustering, the barangay is under the North Central Cluster along with other four (4) barangays – Guadalupe Nuevo, Pitogo, Pinagkaisahan, and South Cembo. The land area of Post Proper Southside covers 12.5% (3.412 square kilometers) of Makati, and is the largest among the 33 barangays.
Given the largest share on land area, it also houses a total of 45,310 residents, as per 2010 Census of Population by NSO or an estimated of 9,062 households - the highest population count as compared with other barangays in Makati. Average population density, on this note, is only at 13 people per 1,000 square meters given the greater chunk occupied by the American Cemetery (601,000 sqm.), and the commercialized part of the Bonifacio Global City.