Mass Underground South Boston
Boston · last checked Sep 27, 2026 · Report a wrong detail
- Cold plunge
Membership required. This place doesn't sell single visits or day passes.
The site says it is members only and does not offer day passes (South Boston and Charlestown).
- Day pass
- None: membership required
- Sauna type
- No sauna listed
- Hours
Monday 4:30 am to 10:30 pm Tuesday 4:30 am to 10:30 pm Wednesday 4:30 am to 10:30 pm Thursday 4:30 am to 10:30 pm Friday 4:30 am to 10:30 pm Saturday 4:30 am to 10:30 pm Sunday 4:30 am to 10:30 pm
Not published by Mass Underground South Boston: intro offer, membership, plunge temperature, swimsuit, towels, booking.
About prices: Members only. Membership pricing is not published on their website.
Prices from Mass Underground South Boston's website, checked Sep 27, 2026.
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Prices and hours last checked Sep 27, 2026. Something wrong? Tell us.