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                                                                EXHIBIT 4.29


                                 PROMISSORY NOTE


US $82,305,000                                                   April 22, 2001

                  FOR VALUE RECEIVED, WORLDWIDE FIBER HOLDINGS LTD.,
("Borrower"), hereby promises to pay to 360FINANCE LTD. ("Holder") at 1500 -
1066 West Hastings Street, Vancouver, British Columbia, or such other place as
the Holder may notify the Borrower, the principal amount of EIGHTY TWO MILLION
THREE HUNDRED FIVE THOUSAND ($82,305,000), as adjusted from time to time in
accordance with the terms of this Promissory Note (the "Principal Amount"), upon
the earlier of December 22, 2005, and the occurrence of an "Event of Default",
as hereafter defined, together with interest as provided below.

                  This Promissory Note shall bear interest on the Principal
Amount from time to time outstanding hereunder at the rate of 6.20 percent per
annum compounded annually. Interest shall be calculated on the basis of a
365-day year for the actual number of days elapsed and shall accrue from
December 22, 2000 to the date of payment. Interest accrued but unpaid during any
Yearly Period shall become part of the Principal Amount effective at 11:59 P.M.
E.S.T. on the last day of such Yearly Period. As used herein, the term "Yearly
Period" means each successive 12 month period, beginning on December 22, 2000
and ending on December 22, 2001 and continuing to each successive 12 month
period thereafter, during which the Principal Amount or any part thereof remains
outstanding.

                  All payments hereunder shall be made in immediately available
funds in lawful money of the United States of America.

                  This Promissory Note may be prepaid in whole or in part at any
time without premium or penalty.

                  As used herein "Event of Default" has the meaning given
thereto in the General Security Agreement (the "GSA") dated as of April 22, 2001
made by the Borrower in favour of the Holder as security for, inter alia, the
indebtedness and liability of the Borrower to the Holder under this Promissory
Note. The obligations of the Borrower under this Promissory Note are subject to
the terms of the GSA and the Agreement for Transfer of Put Obligations and GBM
Note dated for reference April 22, 2001 among the Holder, the Borrower and
360networks inc..

                  Upon the occurrence of an Event of Default, the Holder shall
have all rights and remedies provided in the GSA.

                  This Promissory Note shall be governed by, and construed in
accordance with, the laws of British Columbia, without giving effect to the
principles of conflict of laws thereof.


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                  This Promissory Note is not negotiable but is assignable by
the Holder subject to the equities between the Borrower and the Holder,
including payments of principal and interest from time to time outstanding
hereunder.

                  Subject to the foregoing, this Promissory Note shall be
binding upon the successors and assigns of the Borrower and shall enure to the
benefit of the Holder and its successors and assigns.



                                       WORLDWIDE FIBER HOLDINGS LTD.

                                       Per:


                                       Signed
                                       _______________________________________
                                       Signature


                                       _______________________________________
                                       Name


                                       _______________________________________
                                       Title



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