University Tie Lines Each extension in the directory is preceded by a tie line code that corresponds to one of the Columbia locations. CALLING FROM MORNINGSIDE (Columbia Campus, Barnard College) 851-xxxx, 853-xxxx, or 854-xxxx To Columbia location: Dial as follows: CX Centrex (280 exchange) Exchange # 92 xxxx MC Columbia University Medical Center (212) 305 = 51 5-xxxx (212) 342 =* 51 2-xxxx (212) 543 =* 51 4-xxxx (212) 426 = 51 6-xxxx IC Interchurch Center 80 xxxx LD Lamont-Doherty Earth Observatory 95 xxxx NL Nevis Labs 72 xxxx TC Teachers College 94 xxxx MS Barnard Dorms 981 xxxx RH Reid Hall 53 xxxx AP Audobon Plaza (Lasker, Russ Berrie, Irving Center for Cancer Research) 1-xxxx * Only (212) 342-, (212) 543-, and (646) 426- NYPH-provided telephones can be reached using the above dialing codes. For other 342- and 543- telephone numbers, you must dial 1+212+ the seven-digit number or 1+646+ the seven-digit number. CALLING FROM COLUMBIA UNIVERSITY MEDICAL CENTER 305-xxxx, 342-xxxx or 543-xxxx To Columbia location: Dial as follows: MS Morningside (Columbia College, Barnard College) 151 x-xxxx AP Audobon Plaza (Lasker, Russ Berrie, Irving Center for Cancer Research) 151 x-xxxx All other locations No tie line available CALLING WITHIN COLUMBIA UNIVERSITY MEDICAL CENTER 305-xxxx, 342-xxxx, 543-xxxx or 932-xxxx To Medical Center location: Dial as follows: MC Columbia University Medical Center (Dialing Plan) (212) 305 = 5-xxxx (212) 342 =* 2-xxxx (212) 543 =* 4-xxxx (212) 932 =* 4-xxxx (646) 462 =* 6-xxxx AP Audobon Plaza (Lasker, Russ Berrie, Irving Center for Cancer Research) 151 x-xxxx * Only (212) 342-, (212) 543-, and (646) 426- NYPH-provided telephones can be reached using the above dialing codes. For other 342- and 543- telephone numbers, you must dial 1+212+ the seven-digit number or 1+646+ the seven-digit number. CALLING FROM INTERCHURCH 870-xxxx To Columbia location: Dial as follows: CX Centrex (280 exchange) 85 92 xxxx MC Columbia University Medical Center 85 51 x-xxxx LD Lamont-Doherty Earth Observatory 85 95 xxxx MS Morningside (Columbia Campus, Barnard College) 85 x-xxxx NL Nevis Labs 85 72 xxxx TC Teachers College 85 94 xxxx AP Audobon Plaza (Lasker, Russ Berrie, Irving Center for Cancer Research) 85 56 x-xxxx CALLING FROM CENTREX 280-xxxx To Columbia location: Dial as follows: CX Columbia University Medical Center 92 51 x-xxxx IC Interchurch Center 92 80 xxxx LD Lamont-Doherty Earth Observatory 92 95 xxxx MS Morningside (Columbia Campus, Barnard College) 92 x-xxxx NL Nevis Labs 92 72 xxxx TC Teachers College 92 94 xxxx AP Audobon Plaza (Lasker, Russ Berrie, Irving Center for Cancer Research) 92 56 x-xxxx CALLING FROM LAMONT-DOHERTY EARTH OBSERVATORY 845-365-xxxx To Columbia location: Dial as follows: MS Morningside (Columbia Campus, Barnard College) 71 x-xxxx All other locations No tie line available CALLING FROM TEACHERS COLLEGE 678-xxxx To Columbia location: Dial as follows: MS Morningside (Columbia Campus, Barnard College) 71 x-xxxx All other locations No tie line available CALLING FROM NEVIS LABS 914-591-xxxx To Columbia location: Dial as follows: MS Morningside (Columbia Campus, Barnard College) 4 x-xxxx All other locations No tie line available.