I love Pavillon de la Reine, on Place des Vosges. It's a charming, boutique hotel with a spectacular location. The Place des Vosges has all its 16th century facades still intact, and is gorgeous. You're an easy walking distance from the Marais district, will all of its museums including Picasso.

Here's the write-up from Fodors:

"This gorgeous place des Vosges mansion dating from 1612 competes with Ritz-level luxury but on a more intimate scale, sans the pomp or potentially intimidating service. Entrez through a cobblestone courtyard into a luscious lobby that recalls a royal hunting lodge: massive beams overhead, tapestries, stone walls, and a salon with the original 300-year-old fireplace. You can reserve a room in the older section, decorated in classy Louis XIII style and perhaps with a canopy bed, or opt for the modern yet reserved wing that has parquet bathroom floors and plush eggplant-color sofas and padded headboards. For an absolutely royal feeling, ask for a duplex with French windows overlooking the flower-filled courtyards. www.pavillon-de-la-reine.com. 31 rooms, 24 suites. "