Short answers, pulled from the story.
The Relic Stupa of Vaishali in Bihar, India emerged during the 5th century BCE when Buddhism first took root on the Indian subcontinent. This structure stands as the earliest archaeologically known stupa.
King Ashoka commissioned a major stupa at Sanchi between 273 and 236 BCE that later became a central pilgrimage site. Four elaborate stone gateways now mark the four cardinal points of this ancient complex after it grew from an original simple structure into a more decorative outer layer over two centuries.
Builders constructed about 45,000 monasteries in China with the brick pagoda at Songyue Monastery in Dengfeng County standing as one of the earliest surviving examples there. Thai temples known as wats typically contain golden chedi towers covered with gold leaf that house relic chambers alongside multiple roof tiers.
A massive stupa took form as an elaborate stepped pyramid at Borobudur in Central Java during the 9th century CE under the Javanese Shailendra dynasty. It covers a total surface area of 2,500 square metres decorated with 2,672 relief panels and 504 Buddha statues while remaining recognized as the largest Buddhist temple in the world today.
Buddhism arrived from the continent via the Three Kingdoms of Korea in the 6th century bringing new building traditions to Japan. Local versions developed gradually to meet Japanese tastes and solve problems posed by rainy humid weather using beam and post structures with elevated floors and hip-and-gable roofs.