<prompt> Translate the following text to EnglishChumba cha chini chini ya mraba huo kina kuta na misingi kutoka enzi za Gallic, Kirumi, na enzi za kati, na maonyesho yaliyobuniwa vizuri juu ya Paris ya mapema.  <response>: The crypt beneath the square contains walls and foundations from the Gallic, Roman, and medieval eras, and a well designed exhibition on early Paris. 