A Latin Quarter speakeasy where the cocktail programme leans whisky-heavy and the soundtrack leans American country.
Castor Club sits on Rue Hautefeuille in the 6e, a four-minute walk from Saint-Michel metro, on a narrow Latin Quarter side street. The bar has run since 2011 under bartender-owner Carina Tsou (ex-ECC), and the format is a two-floor speakeasy — a small ground-floor bar and a downstairs basement room with the country-music programme that gave the place its early reputation.
Le Fooding and Time Out Paris both flagged Castor Club in their early-2010s Paris cocktail-bar reappraisals, and The Infatuation Paris has kept it on its Saint-Germain neighbourhood list every year. The basement is where the room earns its name — cosy, candle-lit, no phone signal, and a curated American whisky shelf that punches well above the 6e average.
Two rooms. The ground floor has eight bar seats and a few tables; the basement, accessed via a narrow staircase, seats around 30 across small banquettes and runs the music programme. Google Maps reviewers (n=520) note that the basement is the room to ask for, and that the ground floor is essentially a holding pen on a busy night. The basement runs warm; coats off is the norm.
Order the Castor Old Fashioned (€14) built with rye and a house orange bitter, and the Whisky Sour (€13) with egg white. The bar's signature is the Penicillin (€15), which Le Fooding singled out as “a more honest Penicillin than most Paris bars manage”. Skip the wine list; the room is built around brown spirits. r/paris regulars consistently mention the seasonal whisky punch as a worthwhile order for a group of two or three.
Saint-Germain locals and Sciences Po crowd until 10pm; a more mixed late-night crowd in the basement after midnight. The Infatuation Paris noted in a 2024 feature that the room “keeps its tempo unusually well past midnight for a 6e bar”. Best first-visit window is 8pm to 10pm on a Tuesday or Wednesday for basement availability without a wait.
Reservations are taken via phone only and the bar does not run an online booking system; calling between 5pm and 7pm is the most reliable window. Walk-ins are accommodated upstairs almost any night; the basement fills first and clears slower. Card and contactless both work; tipping is appreciated but not expected. The bar shuts on Sundays and Mondays year-round and closes for the last two weeks of August. The kitchen runs a very short bar-snacks menu until 1am, mostly cheese and charcuterie plates priced €8 to €15. The bar accepts foreign cards and the English-language ordering is fluent. Smoking is not permitted on either floor and the staircase is narrow, steep, and unmarked from the street level — r/paris regulars consistently warn first-time visitors that the door looks closed even when the bar is in full swing. The country-music programme is louder in the basement than first-time visitors expect; the ground floor runs quieter and is the seat for a conversation. Tipping is appreciated but not expected.
Castor Club's official site (verified May 2026); Le Fooding; Time Out Paris; The Infatuation Paris; r/paris; Google Maps reviews (n=520).