Every now and then I see people, often in groups, wandering around Paris as if on a treasure hunt. It turns out they are on a treasure hunt! July 3 is the next hunt for the eternal roses. “La Chasse aux trésors – de Paris” is coordinated with the Mayor of Paris’ office. It is a game complete with rules and prizes. The hunt begins between 10 a.m. an 1 p.m. and ends promptly at 3:30 p.m. It begins in front of the city halls for the following arrondissements: 3, 6, 9, 11, 12, 13, 18, 19, 20 and Saint Ouen. How do you find a city hall? If you…