I remember a summer vacation when we visited the Padmanabhapuram Palace - https://www.padmanabhapurampalace.org/ https://www.padmanabhapurampalace.org/ . It was

I remember a summer vacation when we visited the Padmanabhapuram Palace - https://www.padmanabhapurampalace.org/ https://www.padmanabhapurampalace.org/ . It was a very hot day. But as soon as we entered the palace the cool atmosphere made us feel comfortable. Despite there being no electric fan or air conditioning, and not much noticeable breeze inside, the temperature was noticeably cooler. The elders in the family pointed out to us kids that it was because of the architecture and material used in building the palace. The memory and the ingenuity of it all stuck with me as a kid as I didn't understand how a building could be cool without fan or ac.