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                                                                   Exhibit 10.29





                      MACQUARIE INFRASTRUCTURE COMPANY LLC





                                     - and -





                               BALFOUR BEATTY PLC





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                            PARENT COMPANY GUARANTEE

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THIS GUARANTEE is made the [0] day of [0], 2004

BETWEEN:

(1)      MACQUARIE INFRASTRUCTURE COMPANY LLC, whose principal executive office
         is at 600 Fifth avenue, 21st floor, 10020 NY, USA (formerly Macquarie
         Infrastructure Assets LLC) (hereinafter called "MICL" or the
         "Guarantor"); and

(2)      BALFOUR BEATTY PLC, whose registered office is at 130 Wilton Road,
         London SW1W 1LQ (hereinafter called "BB").

WHEREAS:

(A)      Under a parent company guarantee dated 26 March 1996, as amended and
         restated on 30 April 2003, between BB and Macquarie European
         Infrastructure Plc ("MEIP") (the "Parent Company Guarantee"), MEIP
         agreed to guarantee (1) the due performance by Macquarie Yorkshire
         Limited ("MYL") of a shareholders' agreement dated 26 March 1996, as
         amended and restated on 30 April 2003, between MYL, BB, Yorkshire Link
         (Holdings) Limited ("YLHL"), Yorkshire Link Limited ("YLL") and MEIP
         (the "Shareholders' Agreement") and (2) the due performance by
         Macquarie Infrastructure (UK) Limited ("MIUK") of a technical services
         agreement dated 26 March 1996 between YLL, MIUK and BB (the "Technical
         Services Agreement") and a secondment agreement dated 26 March 1996, as
         amended and restated on 30 April 2003, between YLL, BB and MIUK (the
         "Secondment Agreement").

(B)      On 10 March 2004 the Technical Services Agreement was terminated.

(C)      YLL changed its name to Connect M1-A1 Limited on 2 June 2004
         ("Connect"); YLHL changed its name to Connect M1-A1 Holdings Limited
         ("Connect Holdings") on 2 June 2004.

(D)      Pursuant to a share purchase agreement entered into between MEIP and
         MICL on or around the date hereof (the "Share Purchase Agreement"),
         MEIP will sell and MICL will purchase the 5,000,000 ordinary shares
         owned by MEIP in MYL (the "Transaction").

(E)      Prior to Completion (as defined in the Share Purchase Agreement), MICL
         intends to notify MEIP that it wishes to nominate Macquarie Yorkshire
         LLC ("MY LLC") as the transferee of the Shares (as defined in the Share
         Purchase Agreement) pursuant to paragraph 1 of Schedule 5 of the Share
         Purchase Agreement.

(F)      As a result of the Transaction MEIP wished to be released and
         discharged from the Shareholders' Agreement and the parties agreed to
         the novation of the Shareholders' Agreement. BB, MEIP, MYL, Connect,
         Connect Holdings, MY LLC and MICL entered into a deed of novation of
         the Shareholders' Agreement on or around the date hereof (the
         "Shareholders' Agreement Novation") pursuant to which the Shareholders'
         Agreement was terminated and replaced by a replacement shareholders'
         agreement between BB, MY LLC, MYL, Connect and Connect Holdings (the
         "Replacement Shareholders' Agreement").

(G)      As a result of the Transaction MIUK wished to be released and
         discharged from the Secondment Agreement and the parties agreed to the
         novation of the Secondment Agreement. BB, MIUK, Connect, MYL and MICL
         entered into a deed of novation of the Secondment Agreement on or
         around the date hereof (the "Secondment Agreement Novation") pursuant
         to which the Secondment Agreement was terminated and replaced by a
         replacement secondment agreement between BB, MYL and Connect (the
         "Replacement Secondment Agreement").

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(H)      On or around the date hereof, BB entered into a deed of release with
         MEIP under which MEIP was released from its obligations under the
         Parent Company Guarantee.

(I)      Pursuant to the Replacement Shareholders' Agreement, the parties have
         agreed to enter into this guarantee and the Guarantor has agreed to
         guarantee to BB (1) the due performance by MY LLC of its obligations
         under the Shareholders' Agreement Novation and (2) the due performance
         by MYL of its obligations under the Replacement Shareholders'
         Agreement, the Secondment Agreement Novation, and the Replacement
         Secondment Agreement (together the "Relevant Contracts").

NOW THIS DEED WITNESSES as follows:

1.       The Guarantor hereby unconditionally and irrevocably guarantees to and
         covenants with BB that:

         (a) MYL and MY LLC will well and truly perform and observe all
             obligations, terms, provisions, conditions and stipulations
             mentioned or described in the Relevant Contracts to which they are
             a party or to be implied therefrom on its/their part to be so
             performed and observed according to the true purport, intent and
             meaning hereof; and

         (b) if for any reason whatsoever and in any way MYL or MY LLC shall
             fail to perform the same, then the Guarantor shall, upon receipt of
             a notice in writing from BB, take over from MYL or MY LLC (as
             appropriate) and shall forthwith perform and observe or cause to be
             performed and observed such obligations, terms, provisions,
             conditions and stipulations as aforesaid so far as and to the
             extent MYL or MY LLC (as appropriate) was liable to perform and
             observe them and shall to the same extent be responsible to BB as
             principal and not merely as surety for MYL or MY LLC (as
             appropriate) for the payment by them of all sums of money, losses,
             damages, costs, charges and expenses that may become due or payable
             to BB by reason or in consequence of the acts or defaults of MYL or
             MY LLC (as appropriate) in the performance or observance of the
             Relevant Contracts.

         Provided that under no circumstance whatsoever shall the liabilities of
         the Guarantor, MYL and MY LLC pursuant to this Guarantee and the
         Relevant Contracts either individually or when aggregated together
         hereunder exceed the liability which MYL or MY LLC has under the
         Relevant Contracts.

         Such notices as aforesaid shall be signed by Christopher R. O'N.
         Pearson, Company Secretary of BB, a copy of whose signature is attached
         hereto as Schedule 1 (or his respective successor in post whose name
         and specimen signature must be advised to the Guarantor and
         authenticated by the Company Secretary of BB for the time being).

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2.       Notices in writing of such failure to perform as aforesaid may from
         time to time be sent by BB to the Guarantor at 600 Fifth Avenue, 21st
         Floor, 10020 NY, USA by either registered mail (and shall be regarded
         as being received personally by the Guarantor five days after their
         posting by BB) or delivered personally to the Guarantor at its
         aforementioned address and regarded as delivered at the time of
         delivery. Each notice of such failure to perform shall specify the
         failure.

3.       As between BB and the Guarantor notices in writing of default as
         aforesaid shall be conclusive evidence of MYL's or MY LLC's default in
         performance or observance of any of their outstanding obligations under
         the Relevant Contracts.

4.       The obligations of the Guarantor hereunder are primary and not by way
         of surety only and the Guarantor shall not be entitled as against MYL
         or MY LLC to any right of set off or counterclaim whatsoever and
         howsoever arising.

5.       This Guarantee is irrevocable and shall not be assigned by either
         party.

6.       The Guarantor shall not in any way be released or discharged or
         otherwise absolved of liability hereunder by reason of any of the
         following (whether or not the Guarantor has notice thereof):

         (a) any alteration amendment or variation in the terms of the Relevant
             Contracts;

         (b) any indulgence forgiveness or forbearance shown by BB towards MYL
             or MY LLC whether as to payment or time for payment of any
             arrangement entered into or composition accepted by BB or otherwise
             modifying (by operation of law or otherwise) the rights and
             remedies of BB under the Relevant Contracts or hereunder with
             regard to payment or time for payment or otherwise changing the
             obligations of either party under the Relevant Contracts;

         (c) any action lawfully taken by BB to determine the Relevant
             Contracts;

         (d) any change in the relationship between the Guarantor and MYL or MY
             LLC;

         (e) any disability or incapacity or change in status or constitution of
             MYL, MY LLC or the Guarantor;

         (f) the liquidation or dissolution or insolvency of any of the parties
             referred to herein or any receivership administration moratorium
             composition of creditors claims or other analogous event effecting
             such parties or any of their property or assets; and

         (g) any failure or delay to assert any of BB's rights under this
             Guarantee.

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7.       Any waiver by BB of the terms of this Guarantee or any consent or
         approval given by BB shall only be effective if given in writing and
         then only for the purpose and upon the terms and conditions if any on
         which it is given.

8.       If at any time one or more of the provisions of this Guarantee is or
         becomes invalid or otherwise unenforceable in any respect neither the
         validity or enforceability of the remaining provisions of this
         Guarantee nor the validity or enforceability of such provision under
         the law shall in any way be affected or impaired as a result.

9.       Terms and conditions used in this Guarantee shall bear the same meaning
         as in the Replacement Shareholders' Agreement where such have a
         specific meaning ascribed to them.

10.      The Guarantor shall at all times maintain an agent for service of
         process and any other documents in proceedings in England or any other
         proceedings in connection with this guarantee. Such agent shall be MYL
         of Level 29 and 30, 1 Ropemaker Street, London EC2Y 9HD and any
         judgment or other notice of legal process shall be sufficiently served
         on the Guarantor if delivered to such agent at its address for the time
         being. The Guarantor agrees to inform BB in writing of any change of
         address of such process agent within 28 days of such change. If such
         process agent ceases to be able to act as such or to have an address in
         England, the Guarantor irrevocably agrees to appoint a new process
         agent in England and to deliver to BB within 14 days a copy of a
         written acceptance of appointment by the process agent.

11.      This Deed shall be governed by and construed in accordance with the
         laws of England and shall be submitted to the exclusive jurisdiction of
         the English Courts.



In witness whereof the Guarantor and BB have executed this document as a Deed
the day and year first before written.

MACQUARIE INFRASTRUCTURE ASSETS LLC

EXECUTED and DELIVERED by [o] as              )
[authorised signatory] on behalf of           )    ----------------------------
Macquarie Infrastructure Company LLC and      )
thereby executed by it as a Deed              )



BALFOUR BEATTY PLC

EXECUTED as a Deed by Balfour Beatty PLC      )
acting by and                                 )    -----------------------------
                                              )    Director
                                              )

                                                   -----------------------------
                                                   Director/Secretary


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                                   SCHEDULE 1

          Specimen Signature of Company Secretary of Balfour Beatty plc



The following signature is the specimen signature of the Company Secretary of
Balfour Beatty plc who is authorised to issue notices under paragraph 1(b) of
the Parent Company Guarantee:

Name:    C.R. O'N Pearson               Signature:   [Sgd CC.R. O'N Pearson]

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