Where does “nástupiště” come from?

nástupiště (Czech) comes from Czech nástup, from Czech nastoupit, from Czech ná-, from Old Czech na-, from Proto-Slavic na- — on.

nástupiště (Czech): platform

Definitions

Step	Language	Word	Meaning
1	Czech	nástup	getting on; muster
2	Czech	nastoupit	—
3	Czech	ná-	—
4	Old Czech	na-	—
5	Proto-Slavic	na-	on

nástupiště — Etymology, Origin & Word History | Etymology Explorer