travel planning; travel plans
Refers to the act of planning a trip or the resulting itinerary/schedule. Common in both casual and formal contexts.
I like making travel plans for summer vacation.
We had to change our travel plans.
旅行 means 'travel' or 'trip' in general, while 旅行計画 specifically refers to the planning or the plans themselves.
計画 is a broader term for 'plan' or 'project'; 旅行計画 narrows it to travel-related planning.
Compound of 旅行 (travel) and 計画 (plan).