By Ramayana ended, I mean to denote the period of time after Valmiki completed writing Ramayana. What happened to sage Valmiki?
Valmiki is still living. He was also present during the conversation between Yudhisthira and Bhishma which is recorded in Anushashana Parva of Mahabharata. For eg. In this chapter of Anushashana Parva, after Lord Krishna finishes reciting Mahadeva Sahasranaama to Yudhisthira and others, among with other sages, Valmiki also comments there as:
Then the illustrious Valmiki, addressing Yudhishthira, said, --Once upon a time, in course of a dialectical disputation, certain ascetics that were possessors of the homa fire denounced me as one guilty of Brahmanicide. As soon as they had denounced me as such, the sin of Brahmanicide, O Bharata, possessed me. I then, for cleansing myself, sought the protection of the sinless Ishana who is irresistible in energy. I become cleansed of all my sins. That dispeller of all sorrows, viz., the destroyer of the triple city of the Asuras, said unto me,-Thy fame shall be great in the world.
If he's still alive where is he right now? Jan 16, 2017 at 14:47
3@sv. I don't think we can exactly know where he is now... he may have went to Vadari as Vyasa went.. or he may be living in other tirthas or mountains like Mandara, Meru etc... It's like asking "Where is Ashwatthama living now if he is still alive?"– TezzJan 16, 2017 at 15:32
"Where is Ashwatthama living now if he is still alive?" -- yes, that's a valid question as well, so we already have: Where is Ashwatthama now and up to which age he will be alive? Jan 16, 2017 at 19:27
"he may have went to Vadari as Vyasa went" -- where's Vadari? Is it a physical place? Jan 16, 2017 at 19:28
@sv. Vadari is that place near to Kailash where Vishnus incarnation Nara and Narayana are still living (eternally dwelling)..see my answer here: hinduism.stackexchange.com/questions/8975/… "Hither, in the asylum, known by the name of Vadari, eternally dwell Krishna who is Narayana's self, and Jishnu that most exalted, of all male beings, and Brahman"– TezzJan 17, 2017 at 1:53
after the end of Treta Yugrather than
after the Ramayana ended.:)