To speak about past holidays or events, we use the simple past:
• Last summer, I went to Italy
• When I was in Japan last year, I visited Mount Fuji
• I walked 8km each day
• I went to visit my Mother last Sunday
• I ate at a different restaurant every evening
To speak about fixed future plans and holidays, we can use the present continuous:
• I'm going to Greece next summer
• We're going to visit Mount Fuji when we're in Japan
• I'm having a party next weekend
• I'm going to the cinema on Friday
• I'm having lunch with some friends on Tuesday