Hello Xavier.
Here's an example:
There is currently an exhibition in my city held in the Niš Synagogue Gallery. The exhibition is open from March 1st to April 1st. But the Gallery has working hours.
It can't really be defined as a museum, since there are rarely any numismatic exhibitions in the gallery. Nor can it be defined as a market, since you cannot buy anything.
My suggestion is to have an option to select a date range of the exhibition and working hours of the gallery that the exhibition is taking place.
The screenshot is showing how it is currently. It is not really correct, since it is open through whole March, not just these 7 days.
The working hours of the galley is:
Monday: closed
Tue-Fri: 10:00-16:00
Weekend: 10:00-15:00