ðˌoʊ ˌɪntɹədˈʌktɚɹi tˈʊɹz wɜː bˌiːɪŋ kəndˈʌktᵻd dˈʊɹɹɪŋ ðə stˈɛɹ kənstɹˈʌkʃən pˈiəɹɪəd, ðə ɡɹˈænd ˈoʊpənɪŋ ʌv blˈæk kˈæzəm tˈʊk plˈeɪs ɪn ˈeɪpɹəl tˈuː θˈaʊzənd wˈʌn.
Though introductory tours were being conducted during the stair construction period, the grand opening of Black Chasm took place in April 2001.