World's biggest Buddhist temple. Spectacular to visit. I visited in Nov 23, so was supposed to be raining and low season, but no rain. It was quite quiet. I stayed in Borobudur rather than Yogyakarta to get there early. 

However, since COVID, regulations have changed. There are NO sunrise tours any more. They now limit the number of people who can go onto the temple to 150 an hour - the earliest entry onto the temple is 9am - you get your ticket to allow you to enter starting from 8:30am. I went at 7am walked around the base of the temple and the grounds, before at 8:30am returning to the entry to get a guide and then return to enter the temple at 9am. There are various levels, with the lower ones have many kms of carvings showing the story of how Siddartha became Buddha. On the top level you have the Stupas themselves, each containing a Buddha. 

Highly reccomended visiting. The museum too is simple but shows interesting photos of 'before' and 'after' - beware, though, if you use the exit from the museum it forces you to walk through hundreds of tourist stalls wihout escape.