On the last days of his life the great Gautam Buddha arrived in kushinagar a small town in state uttar pradesh of india.He decided to leave his body(die) in Kushinagar then one of his fellow asked him to move to some bigger place but he repplied ”no this place is good”.
And when Buddha was about to give up his students requested him not to leave them alone.Then he showed them his body removing the cloth.His body was infected by Diseases and infection and said the following words.
These were the very last words Buddha spoke:
“Behold, O monks, this is my last advice to you. All component things in the world are changeable. They are not lasting. Work hard to gain your own salvation. Do your best.”
Then the Buddha lapsed into the Jhana stages or meditative absorption. Going from level to level, one after the other, ever deeper and deeper. Then he came out of the meditative absorption for the last time. After that he passed into Jhana a little way; and from this Jhana the Buddha passed into Nibbana leaving nothing whatever behind that can cause rebirth again in this or any other world.
The passing away of the Buddha occurred in 543 B.C. on a full-moon day in the month of May, known in the Indian calendar as Vesak.