1. Galeries Lafayette Haussmann — 9th arr. · Boulevard Haussmann
The Art Nouveau glass dome and a free rooftop terrace, plus a Gourmet & Home building.
The store's own page lists three buildings on Boulevard Haussmann: the Coupole store at number 40, the men's store at 48, and the Gourmet & Home building at 35. Hours listed are Monday to Saturday 10 am to 8:30 pm and Sunday 11 am to 8 pm, with the gourmet floor open 9:30 am to 9:30 pm daily. It adds that hours can change on public holidays and during special events.
The page says the rooftop terrace is free, with views of the Eiffel Tower, Sacré-Cœur and the Palais Garnier, though it may close in bad weather. Viewing the glass dome and its decoration is also free. The store quotes a 12% VAT refund for non-EU visitors on purchases over €100.
Good to know: Go up to the terrace on a clear day, and check the page for holiday hours.
40 Boulevard Haussmann, 75009 Paris, France