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- For information: The Crypt of the Basilica of Boulogne-sur-Mer is closed until January 16, 2017 included- Unusual and huge, the crypt is a real maze of rooms and galleries that extend under the entire surface of the Notre-Dame Basilica.

It was built in the 19th century around the remains of the Romanesque crypt rediscovered in 1828. Both Historical Monument decorated with paintings covering the entire walls and vaults, it is also an archaeological site bearing witness to the Roman origins of Boulogne, and a a real museum where are presented a treasure of Sacred Art and a lapidary collection of elements from the old medieval cathedral. The site has just benefited from a restoration and a new museum layout inaugurated on May 30, 2015.

Useful information  


Open Tuesday to Sunday (closed on Mondays)
High season from 2/05 to 30/09 (10am to 6pm)
Low season from 1/10 to 30/04 (10h-12h30 / 14h30-17h30)

Full price: € 5 - Reduced price: € 3

Special rate 1st Sunday of the month: 2 €

Special rate Days fortified sites: 3 €

For more information, visit:

Closing of the crypt on December 25th, January 1st and January 8th to 22nd 2018.

Useful information
Rue de Lille

Phone: +33 (0)3 21 87 81 79


Spoken languages
  • french
Files to download
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Near(by) :
The fortified part of BSM