门票(mén piào) - entrance ticket in Mandarin

门票 (mén piào) is 门 (mén, "door, gate") plus 票 (piào, "ticket"), literally "gate ticket" - the standard word for an admission ticket to a park, museum, zoo or tourist site. 这个公园的门票 (zhège gōngyuán de mén piào), "this park's entrance ticket", is exactly the phrase you would use asking about price at the gate.

门票 (mén piào) is a subtype of the broader word 票 (piào, "ticket"), which also covers 电影票 (diànyǐngpiào, "cinema ticket") and 车票 (chēpiào, "bus/train ticket") - swap the first character and you name a different kind of ticket, a pattern that repeats across the whole family.

At many sites in China, 门票 (mén piào) is sometimes 免费 (miǎnfèi, "free of charge") for children, students or on certain public holidays, so it is worth asking 门票多少钱 (mén piào duōshǎo qián), "how much is the entrance ticket", rather than assuming a price.