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                                                                   EXHIBIT 10.17

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                      FIRST MODIFICATION TO LOAN AGREEMENT

                                     among

                   STARWOOD HOTELS & RESORTS WORLDWIDE, INC.,

                               HARBOR-CAL S. D.,

                     STARWOOD SHERATON SAN DIEGO CMBS I LLC

                                       and

                         SLT REALTY LIMITED PARTNERSHIP

                    -----------------------------------------

                          Dated as of January 27, 1999

                    -----------------------------------------

                                  $100,000,000

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            FIRST MODIFICATION TO LOAN AGREEMENT, dated as of January 27, 1999
("First Modification"), among STARWOOD HOTELS & RESORTS WORLDWIDE, INC., a
Maryland corporation (the "Borrower"), SLT REALTY LIMITED PARTNERSHIP, a
Delaware limited partnership (the "Lender"), successor-in-interest to Starwood
Hotels & Resorts, a Maryland real estate investment trust (the "Trust"),
HARBOR-CAL S.D., a California joint venture ("Harbor-Cal"), and STARWOOD
SHERATON SAN DIEGO CMBS I LLC, a Delaware limited liability company (the
"Guarantor"). Unless otherwise defined herein, all capitalized terms used herein
shall have the respective meanings provided such terms in the Loan Agreement
referred to below.

                                   WITNESSETH:

            WHEREAS, the Trust has previously made a loan to the Borrower in the
maximum principal amount of $100,000,000 (the "Loan") pursuant to that certain
Loan Agreement, dated as of February 23, 1998 (as amended, supplemented or
otherwise modified from time to time, the "Loan Agreement"), as assigned by the
Trust to the Lender pursuant to that certain General Assignment dated as of
February 23, 1998 and as evidenced by that certain Promissory Note, dated as of
February 23, 1998 (as may be amended from time to time, the "Note");

            WHEREAS, in connection with the Loan Agreement, Harbor-Cal executed
a certain Leasehold Deed of Trust, Security Agreement, Financing Statement and
Fixture Filing, dated as of February 23, 1998, in favor of the Trust and
covering a portion of the premises known as the Sheraton San Diego Hotel &
Marina (the "Sheraton San Diego Property"), as assigned to Lender pursuant to
that certain Assignment of Mortgage dated as of February 23, 1998 (the "Sheraton
San Diego Deed of Trust");

            WHEREAS, the Guarantor and certain subsidiaries of the Trust and the
Borrower are entering into a certain Loan Agreement dated as of January 27, 1999
and among the borrowers named therein, Starwood Operator I LLC and Lehman
Brothers Holdings Inc. d/b/a Lehman Capital, a division of Lehman Brothers
Holdings Inc., as lender (the "CMBS Lender") (as amended from time to time, the
"CMBS Loan Agreement");

            WHEREAS, in connection with the transactions contemplated under the
CMBS Loan Agreement, Harbor-Cal has executed an Amended and Restated Leasehold
Deed of Trust, Security Agreement, Financing Statement and Fixture Filing dated
as of January 27, 1999 (the "Amended and Restated Leasehold Deed of Trust"),
amending and restating the Sheraton San Diego Deed of Trust to provide for,
among other things, a limit on the indebtedness secured by the Amended and
Restated Leasehold Deed of Trust to an amount which, when added to the
indebtedness allocable under the CMBS Loan Agreement to the Sheraton San Diego
Property and the amount secured by that certain Amended and Restated Leasehold
Deed of Trust, Security Agreement, Financing Statement and Fixture Filing, dated
the date hereof and executed by Harbor-Cal (the "Amended and Restated Leasehold
Deed of Trust (West Tower)"), shall not exceed the total market value of the
Sheraton San Diego Property;

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         WHEREAS, in connection with the transactions contemplated under the
CMBS Loan Agreement, the parties hereto desire to modify the Loan Agreement to
provide for, among other things, (i) the guaranty by the Guarantor for all
payments due and payable under the Note on a non-recourse basis, (ii) the
extension of the Final Maturity Date of the Loan to February 23, 2014 and,
additionally, the further extension of the Final Maturity Date of the Loan upon
any extension of the maturity date of the loan advanced under the CMBS Loan
Agreement, and (iii) the amendment of certain definitions under the Loan
Agreement.

         NOW, THEREFORE, the parties hereto have agreed as follows:

            1. All references to "Final Maturity Date" under the Loan Agreement
shall hereby be amended to mean "February 23, 2014". Moreover, upon the exercise
of any option to extend the maturity date of the loan under the CMBS Loan
Agreement (the "CMBS Loan Maturity Date Extension"), the Final Maturity Date
under the Loan Agreement shall be further extended to February 23, 2029 or one
(1) year beyond any such CMBS Loan Maturity Date Extension, whichever shall be a
later date.

            2. All references to "Mortgage" under the Loan Agreement shall
hereby be modified to mean the Amended and Restated Leasehold Deed of Trust.

            3. The parties hereto acknowledge and agree that, notwithstanding
anything to the contrary contained herein, the outstanding principal balance of
the Note, together with all accrued and unpaid interest thereon and all other
sums due in connection therewith (the "Guaranteed Amount"), secured by the
Amended and Restated Leasehold Deed of Trust shall not exceed an amount which,
when combined with (i) the outstanding principal balance, with interest thereon,
of the loan advanced pursuant to the CMBS Loan Agreement and allocable to the
Sheraton San Diego Property, together with the amount of all other Permitted
Indebtedness (as defined in the CMBS Loan Agreement) on the Sheraton San Diego
Property under the CMBS Loan Agreement, and (ii) the amount secured by the
Amended and Restated Leasehold Deed of Trust (West Tower), shall not exceed one
hundred percent (100%) of the total market value of the Sheraton San Diego
Property.

            4. The parties hereto acknowledge and agree that the Guarantor shall
guarantee to the Lender full and prompt payment when due of the principal of,
and interest on, the Guaranteed Amount. The liability and obligation of the
Guarantor or any member, officer, director, successor or assign of the
Guarantor, to perform and observe and fulfill its obligations set forth
hereunder shall not be enforced by any action or proceeding wherein damages or
any money judgment or any deficiency judgment or any judgment establishing any
personal obligation or liability shall be sought, collected or otherwise
obtained against the guarantor or any of its officers, members, directors,
partners, successors or assigns, it being agreed that the Lender shall only look
to the interest of the Guarantor in the Sheraton San Diego Property for the
satisfaction of any obligation of the Guarantor hereunder.

                                      -2-

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            5. The parties hereto agree that all rights of the Lender to receive
any payments from the Borrower under the Loan Agreement or under any guarantees,
mortgages, other types of security documents or otherwise are and shall continue
to be subject and subordinate in payment to the prior payment in full, in cash,
of (i) all Senior Indebtedness (as defined in the Subordination Agreement (as
defined in the Loan Agreement)) and (ii) the indebtedness outstanding under the
CMBS Loan Agreement (the "CMBS Indebtedness") pursuant to, and in the manner set
forth in, that certain Subordination and Intercreditor Agreement executed and
delivered in connection with the CMBS Loan Agreement (the "CMBS Subordination
Agreement"). All of the terms, covenants and conditions hereof are hereby and
shall continue to be subordinate to all of the terms, covenants and conditions
of the Senior Indebtedness and the CMBS Indebtedness. The foregoing shall apply,
notwithstanding the availability of other collateral to the Senior Creditors (as
defined in the Subordination Agreement) or to the CMBS Lender or the actual date
and time of execution, delivery, recordation, filing or perfection of any of the
Senior Indebtedness or the CMBS Indebtedness, or the lien or priority of payment
thereof, and in any instance wherein the Senior Indebtedness or CMBS
Indebtedness or any claim for the Senior Indebtedness or CMBS Indebtedness is
subordinated, avoided or disallowed, in whole or in part, under Title 11 of the
United States Code (the "Bankruptcy Code") or other applicable federal or state
law.

            6. The terms and provisions of this First Modification shall be
binding upon and inure to the benefit of the parties and their respective
successors and assigns.

            7. This First Modification shall be governed by and construed in
accordance with the laws of the State of New York without giving effect to
principles of conflicts of laws.

            8. This First Modification may be signed in any number of
counterparts, each of which shall be an original, with the same effect as if the
signatures thereto and hereto were upon the same instrument.

            9. The parties hereto acknowledge and agree that the name "Starwood
Hotels & Resorts" is a designation of the Trust and its trustees (as trustees
but not personally) under a Declaration of Trust dated August 25,1969, as
amended and restated as of June 6, 1988 and as further amended and restated as
of January [6], 1999, and as the same has been or may be amended from time to
time thereafter, and that the parties hereto shall look solely to the Trust's
assets for the enforcement of any claims against the Trust, as the trustees,
officers, agents and security holders of the Trust assume no personal liability
for obligations entered into on behalf of the Trust, and their respective
individual assets shall not be subject to the claims of any person relating to
such obligations. The foregoing shall govern all direct and indirect obligations
of the Trust under this First Modification.

                                      -3-

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      IN WITNESS WHEREOF, each of the parties hereto has caused a counterpart of
this First Modification to be duly executed and delivered as of the date first
above written.

                         BORROWER:

                         STARWOOD HOTELS & RESORTS WORLDWIDE,
                         INC., a Maryland corporation

                         By: /s/ Jonathan H. Yellen
                             ---------------------------------------
                             Name: Jonathan H. Yellen
                             Title: Authorized Signatory

                         LENDER:

                         SLT REALTY LIMITED PARTNERSHIP,
                         a Delaware limited partnership

                         By: Starwood Hotels & Resorts, a Maryland real estate
                             investment trust, its general partner

                             By: /s/ Jonathan H. Yellen
                                 -----------------------------------
                                 Name: Jonathan H. Yellen
                                 Title: Authorized Signatory

                         HARBOR-CAL S. D.,
                         a California joint venture

                         By: Sheraton Harbor Island Corporation,
                             Its joint venture partner

                             By: /s/ Jonathan H. Yellen
                                 -----------------------------------
                                 Name:  Jonathan H. Yellen
                                 Title: Authorized Signatory

                         By: Sheraton California Corporation,
                             Its joint venture partner

                             By: /s/ Jonathan H. Yellen
                                 -----------------------------------
                                 Name: Jonathan H. Yellen
                                 Title: Authorized Signatory

                                      -4-
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                             GUARANTOR:

                             STARWOOD SHERATON SAN DIEGO CMBS I LLC,
                             a Delaware limited liability company

                             By: /s/ Jonathan H. Yellen
                                 -----------------------------------------------
                                 Title: Authorized Signatory