When reminiscing about the past, it's common to use the phrase "look back at." However, if you're looking for some synonyms for this phrase to switch things up, here are some alternatives.
1. Reflect on
2. Revisit
3. Recollect
4. Review
5. Remember
6. Retrospect
7. Reminisce
8. Turn back the clock
9. Take a trip down memory lane
10. Harken back to
All of these options convey the idea of reflecting on past experiences or memories, but can add variety and nuance to your language.