SUPPLEMENTAL INDENTURE (this "Supplemental Indenture"),  dated
as of September 4, 1998, among American Skiing Company Resort  Properties,  Inc.
(the  "Guaranteeing  Subsidiary"),  a  subsidiary  of ASC  East,  Inc.  (or  its
permitted  successor),  a Maine  corporation (the "Company"),  the Company,  the
other  Guarantors  (as defined in the  Indenture  referred to herein) and United
States Trust Company of New York,  as trustee  under the  indenture  referred to
below (the "Trustee").

                               W I T N E S S E T H

                  WHEREAS,  the Company has heretofore executed and delivered to
the Trustee an indenture (the "Indenture"),  dated as of June 28, 1996 providing
for the issuance of an aggregate  principal amount of up to  $120,000,000.00  of
12% Notes due 2006 (the "Notes");

                  WHEREAS,   the   Indenture   provides   that   under   certain
circumstances  the  Guaranteeing  Subsidiary  shall  execute  and deliver to the
Trustee a supplemental  indenture pursuant to which the Guaranteeing  Subsidiary
shall unconditionally guarantee all of the Company's Obligations under the Notes
and the  Indenture  on the terms and  conditions  set forth  herein  (the  "Note
Guarantee"); and

                  WHEREAS,  pursuant  to  Section  9.01  of the  Indenture,  the
Trustee is authorized to execute and deliver this Supplemental Indenture.

                  NOW THEREFORE, in consideration of the foregoing and for other
good and valuable  consideration,  the receipt of which is hereby  acknowledged,
the Guaranteeing  Subsidiary and the Trustee mutually covenant and agree for the
equal and ratable benefit of the Holders of the Notes as follows:

     1.  Capitalized  Terms.  Capitalized  terms used herein without  definition
shall have the meanings assigned to them in the Indenture.

                  2. Agreement to Guarantee.  The Guaranteeing Subsidiary hereby
agrees as follows:

                  (a)      Along with all Guarantors named in the Indenture,  to
                           jointly and  severally  Guarantee to each Holder of a
                           Note  authenticated  and delivered by the Trustee and
                           to  the  Trustee  and  its  successors  and  assigns,
                           irrespective  of the validity and  enforceability  of
                           the  Indenture,  the Notes or the  obligations of the
                           Company hereunder or thereunder, that:

                           (i)      the  principal  of and interest on the Notes
                                    will be  promptly  paid in  full  when  due,
                                    whether  at   maturity,   by   acceleration,
                                    redemption or otherwise, and interest on the
                                    overdue  principal  of and  interest  on the
                                    Notes,  if any,  if  lawful,  and all  other
                                    obligations of the Company to the Holders or
                                    the Trustee  hereunder or thereunder will be
                                    promptly paid in full or  performed,  all in
                                    accordance   with  the  terms   hereof   and
                                    thereof; and

                           (ii)     in case of any  extension of time of payment
                                    or renewal of any Notes or any of such other
                                    obligations, that same will be promptly paid
                                    in full when due or performed in  accordance
                                    with the terms of the  extension or renewal,
                                    whether at stated maturity,  by acceleration
                                    or  otherwise.  Failing  payment when due of
                                    any amount so guaranteed or any  performance
                                    so  guaranteed  for  whatever  reason,   the
                                    Guarantors  shall be jointly  and  severally
                                    obligated to pay the same immediately.

                  (b)      The  obligations  hereunder  shall be  unconditional,
                           irrespective   of   the   validity,   regularity   or
                           enforceability  of the  Notes or the  Indenture,  the
                           absence of any action to enforce the same, any waiver
                           or consent by any Holder of the Notes with respect to
                           any provisions hereof or thereof, the recovery of any
                           judgment  against the Company,  any action to enforce
                           the  same  or  any  other  circumstance  which  might
                           otherwise  constitute a legal or equitable  discharge
                           or defense of a guarantor.


                  (c)      The following is hereby waived:diligence presentment,
                           demand of  payment,  filing of claims with a court in
                           the event of insolvency or bankruptcy of the Company,
                           any right to require a proceeding  first  against the
                           Company, protest, notice and all demands whatsoever.


                  (d)      This Note Guarantee shall not be discharged except by
                           complete performance of the obligations  contained in
                           the Notes and the Indenture.


                  (e)      If any Holder or the Trustee is required by any court
                           or   otherwise   to  return  to  the   Company,   the
                           Guarantors, or any Custodian,  Trustee, liquidator or
                           other similar  official  acting in relation to either
                           the  Company or the  Guarantors,  any amount  paid by
                           either  to the  Trustee  or such  Holder,  this  Note
                           Guarantee,  to  the  extent  theretofore  discharged,
                           shall be reinstated in full force and effect.


                  (f)      The Guaranteeing  Subsidiary shall not be entitled to
                           any right of  subrogation  in relation to the Holders
                           in respect of any obligations guaranteed hereby until
                           payment in full of all obligations guaranteed hereby.


                  (g)      As between the  Guarantors,  on the one hand, and the
                           Holders and the Trustee,  on the other hand,  (x) the
                           maturity of the obligations  guaranteed hereby may be
                           accelerated as provided in Article 6 of the Indenture
                           for   the   purposes   of   this   Note    Guarantee,
                           notwithstanding   any  stay,   injunction   or  other
                           prohibition  preventing such  acceleration in respect
                           of the obligations  guaranteed hereby, and (y) in the
                           event  of any  declaration  of  acceleration  of such
                           obligations   as   provided   in  Article  6  of  the
                           Indenture,  such obligations  (whether or not due and
                           payable)  shall  forthwith  become due and payable by
                           the   Guarantors   for  the   purpose  of  this  Note
                           Guarantee.


                  (h)      The   Guarantors   shall   have  the  right  to  seek
                           contribution from any non-paying Guarantor so long as
                           the exercise of such right does not impair the rights
                           of the Holders under the Guarantee.


                  (i)      Pursuant  to Section  10.02 of the  Indenture,  after
                           giving  effect to any  maximum  amount  and any other
                           contingent  and fixed  liabilities  that are relevant
                           under  any   applicable   Bankruptcy   or  fraudulent
                           conveyance  laws,  and  after  giving  effect  to any
                           collections from, rights to receive contribution from
                           or  payments  made  by  or on  behalf  of  any  other
                           Guarantor in respect of the obligations of such other
                           Guarantor  under  Article 10 of the  Indenture  shall
                           result in the obligations of such Guarantor under its
                           Note Guarantee not constituting a fraudulent transfer
                           or conveyance.

                  3 EXECUTION AND DELIVERY.  Each Guaranteeing Subsidiary agrees
that the Note Guarantees  shall remain in full force and effect  notwithstanding
any failure to endorse on each Note a notation of such Note Guarantee.

                                                                                
                    4. Guaranteeing Subsidiary May Consolidate,  Etc. on Certain
Terms.

         (a)      The Guaranteeing  Subsidiary may not consolidate with or merge
                  with or into  (whether or not such  Guarantor is the surviving
                  Person) another  corporation,  Person or entity whether or not
                  affiliated with such Guarantor unless:

                  (i)      subject to Section 10.05 of the Indenture, the Person
                           formed  by or  surviving  any such  consolidation  or
                           merger (if other  than a  Guarantor  or the  Company)
                           unconditionally  assumes all the  obligations of such
                           Guarantor,  pursuant to a  supplemental  indenture in
                           form and  substance  reasonably  satisfactory  to the
                           Trustee,  under the Notes, the Indenture and the Note
                           Guarantee  on the terms set forth  herein or therein;
                           and

                    (ii) immediately after giving effect to such transaction, no
Default or Event of Default exists.


          (b) In case of any such consolidation,  merger, sale or conveyance and
upon the assumption by the successor  corporation,  by  supplemental  indenture,
executed and delivered to the Trustee and  satisfactory  in form to the Trustee,
of the  Note  Guarantee  endorsed  upon  the  Notes  and the  due  and  punctual
performance  of all of the  covenants  and  conditions  of the  Indenture  to be
performed by the Guarantor,  such successor  corporation shall succeed to and be
substituted  for the  Guarantor  with the same  effect  as if it had been  named
herein as a Guarantor.  Such  successor  corporation  thereupon  may cause to be
signed any or all of the Note  Guarantees  to be endorsed  upon all of the Notes
issuable  hereunder which  theretofore shall not have been signed by the Company
and  delivered to the Trustee.  All the Note  Guarantees  so issued shall in all
respects  have the same legal rank and benefit  under the  Indenture as the Note
Guarantees theretofore and thereafter issued in accordance with the terms of the
Indenture as though all of such Note  Guarantees  had been issued at the date of
the execution hereof.

                  (c) Except as set forth in Articles 4 and 5 of the  Indenture,
and  notwithstanding  clauses  (a)  and  (b)  above,  nothing  contained  in the
Indenture or in any of the Notes shall prevent any  consolidation or merger of a
Guarantor  with or into the Company or another  Guarantor,  or shall prevent any
sale  or   conveyance  of  the  property  of  a  Guarantor  as  an  entirety  or
substantially as an entirety to the Company or another Guarantor.

                           5.       Releases.

          (a)       In the  event of a sale or other  disposition  of all of the
                    assets of any Guarantor, by way of merger,  consolidation or
                    otherwise,  or a sale  or  other  disposition  of all to the
                    capital stock of any Guarantor,  then such Guarantor (in the
                    event  of a sale or  other  disposition,  by way of  merger,
                    consolidation  or otherwise,  of all of the capital stock of
                    such  Guarantor) or the  corporation  acquiring the property
                    (in the  event  of a sale  or  other  disposition  of all or
                    substantially  all of the assets of such  Guarantor) will be
                    released  and  relieved  of any  obligations  under its Note
                    Guarantee;  provided  that the Net  Proceeds of such sale or
                    other   disposition  are  applied  in  accordance  with  the
                    applicable  provisions of the Indenture,  including  without
                    limitation  Section 4.10 of the Indenture.  Upon delivery by
                    the Company to the Trustee of an Officers'  Certificate  and
                    an Opinion of Counsel to the effect  that such sale or other
                    disposition  was made by the Company in accordance  with the
                    provisions of the Indenture,  including  without  limitation
                    Section 4.10 of the Indenture, the Trustee shall execute any
                    documents  reasonably  required  in  order to  evidence  the
                    release of any Guarantor from its obligations under its Note
                    Guarantee.

         (b)      Any Guarantor not released from its obligations under its Note
                  Guarantee shall remain liable for the full amount of principal
                  of and interest on the Notes and for the other  obligations of
                  any Guarantor under the Indenture as provided in Article 10 of
                  the Indenture.

                  6. NO  RECOURSE  AGAINST  OTHERS.  No past,  present or future
director,  officer,  employee,   incorporator,   stockholder  or  agent  of  the
Guaranteeing  Subsidiary,  as such, shall have any liability for any obligations
of the  Company  or any  Guaranteeing  Subsidiary  under  the  Notes,  any  Note
Guarantees,  the Indenture or this Supplemental Indenture or for any claim based
on, in respect of, or by reason of, such  obligations  or their  creation.  Each
Holder of the Notes by accepting a Note waives and releases all such  liability.
The waiver and release are part of the  consideration for issuance of the Notes.
Such  waiver  may not be  effective  to  waive  liabilities  under  the  federal
securities  laws  and it is the view of the  Commission  that  such a waiver  is
against public policy.

                  7. NEW YORK LAW TO GOVERN.  THE  INTERNAL  LAW OF THE STATE OF
NEW YORK SHALL GOVERN AND BE USED TO CONSTRUE  THIS  SUPPLEMENTAL  INDENTURE BUT
WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT
THAT THE  APPLICATION  OF THE LAWS OF  ANOTHER  JURISDICTION  WOULD BE  REQUIRED
THEREBY.

                  8.  COUNTERPARTS  The parties may sign any number of copies of
this Supplemental  Indenture.  Each signed copy shall be an original, but all of
them together represent the same agreement.

                  9. EFFECT OF  HEADINGS.  The Section  headings  herein are for
convenience only and shall not affect the construction hereof.

                  10 .THE TRUSTEE.  The Trustee shall not be  responsible in any
manner  whatsoever  for or in respect of the  validity  or  sufficiency  of this
Supplemental  Indenture or for or in respect of the recitals  contained  herein,
all of which  recitals are made solely by the  Guaranteeing  Subsidiary  and the
Company.

<PAGE>


     IN WITNESS  WHEREOF,  the parties  hereto  have  caused  this  Supplemental
Indenture  to be duly  executed  and  attested,  all as of the date first  above
written.

Dated:  September 4, 1998

                 AMERICAN SKIING COMPANY RESORT PROPERTIES, INC.


                 By:  /s/ Christopher E. Howard
                   ----------------------------------------------------------
                    Name: Christopher E. Howard
                    Title: Senior Vice President


                    ASC EAST, INC.


                 By: /s/ Christopher E. Howard
                    ----------------------------------------------------------
                    Name: Christopher E. Howard
                    Title: Senior Vice President


                    [EXISTING GUARANTORS]


                    By:      unable to read signature
                         ______________________________
                            Name:
                            Title


                     [TRUSTEE]
                     as Trustee


                     By:  unable to read signature
                         ______________________________
                             Name:
                             Title: