Question

which monuments were built by the bushddhists

Answer 1

religious monument like monestries were built by the Buddhists.

Answer 2

The initial function of a stupa was the veneration and safe-guarding of the relics of Gautama Buddha. The earliest surviving example of a stupa is in Sanchi (Madhya Pradesh).

In accordance with changes in religious practice, stupas were gradually incorporated into chaitya-grihas (prayer halls). These are exemplified by the complexes of the Ajanta Caves and the Ellora Caves (Maharashtra). The Mahabodhi Temple at Bodh Gaya in Bihar is another well-known example.