To fill in the blanks, imagine a famous place you visited. For example, let's use the Eiffel Tower in Paris.
Email Body:
Hi [Friend's Name],
During the summer holiday, I visited Paris, which is famous for its iconic tower. In [mention something specific like 'the evening'], you can see [mention a view or lights]. There are also [mention other attractions like 'museums and gardens']. I hope I can go back to / you can visit [the city] because it's a beautiful city.
See you soon,
[Your Name]