How do you say have a safe trip in Mandarin?

In Mandarin, you can say "一路平安" (yī lù píng ān) to wish someone a safe trip. This phrase directly translates to "safe journey" and is commonly used in casual conversation. Another option is "祝你旅途愉快" (zhù nǐ lǚ tú yú kuài), which means "wish you a pleasant journey."