I've seen very few Elaphe species alive: the two native species in my country, the common ladder snake (Elaphe scalaris) (Rhinechis), and the very rare Aesculapian snake (Elaphe longissima) (Zamenis), some corn snakes in pet shops (Elaphe guttata) (Pantherophis), the Taiwan beauty snake in Plzen zoo (Elaphe taeniura) (not sure in which "genus" now), and for last this Elaphe rosaliae (Bogertophis) at San Diego, that seems very uninterested in the dead mouse that it have for dinner
I will die for see my favourite species, the Mandarin ratsnake, Elaphe mandarina. My favourite colubrid too.
The Mandarin ratsnake ( Euprepiophis ( Elaphe ) mandarinus ) is kept in 16 public collections in Europe - mainly East European collections. It is however also kept in small numbers in the privat scene and I've seen them already several times - and they are really beautifull !
Lucky you! (But you saw so many species that I don't...) For sure I will find a mandarin ratsnake some day. Maybe once somebody can bring me to Expoterraria (annual exhibit of reptiles and amphibians in my country). But at the moment I have other priorities (Duisburg before the river dolphin dies).
