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                                                                 Exhibit 10.1(a)


         EXECUTION COPY


         FIRST AMENDMENT, dated as of June 28, 1999 (this "First Amendment"), to
the CREDIT AGREEMENT, dated as of March 18, 1999 (the "Credit Agreement"), among
CHARTER COMMUNICATIONS OPERATING, LLC (the "Borrower"), CHARTER COMMUNICATIONS
HOLDINGS LLC, the Lenders parties to the Credit Agreement, the Documentation
Agents and Syndication Agents named therein and THE CHASE MANHATTAN BANK and
NATIONSBANK, N.A., as Administrative Agents (in such capacity, the
"Administrative Agents"). Terms defined in the Credit Agreement shall be used in
this First Amendment with their defined meanings unless otherwise defined
herein.

                              W I T N E S S E T H:

         WHEREAS, the Borrower wishes to amend the Credit Agreement in the
manner set forth herein; and

         WHEREAS, each of the parties hereto is willing to enter into this First
Amendment on the terms and subject to the conditions set forth herein;

         NOW, THEREFORE, in consideration of the premises and for other good and
valuable consideration the receipt and sufficiency of which is hereby
acknowledged, the parties hereto agree as follows:

         SECTION I. AMENDMENTS TO CREDIT AGREEMENT.

                  1. Section 1.1 - Exchange Date. The definition of "Exchange
         Date" contained in Section 1.1 of the Credit Agreement is hereby
         amended and restated in its entirety as follows:

                  "Exchange Date": the date of consummation of any Exchange.

                  2. Section 1.1 - Specified Subordinated Debt. The definition
         of "Specified Subordinated Debt" contained in Section 1.1 of the Credit
         Agreement is hereby amended and restated in its entirety as follows:

                  "Specified Subordinated Debt": any Indebtedness of the
         Borrower issued directly or indirectly to Paul G. Allen or any of his
         Affiliates, so long as such Indebtedness (a) qualifies as Specified
         Long-Term Indebtedness and (b) has terms and conditions substantially
         identical to those set forth in Exhibit I.

                  3. Section 1.1 - New Definitions. The following definitions
         are hereby added to Section 1.1 of the Credit Agreement in the
         appropriate alphabetical order:
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                  "Exchange Excess Amount": as defined in Section 7.5(f).

                  "Excluded Exchange Excess Amount": any Exchange Excess Amount
         determined pursuant to one or more Exchanges consummated after the
         Stage One Closing Date until the aggregate Exchange Excess Percentages
         equal 15%. For the purposes of this definition, the "Exchange Excess
         Percentage" with respect to any Exchange that results in an Exchange
         Excess Amount shall equal the quotient (expressed as a percentage) of
         such Exchange Excess Amount divided by Annualized Pro Forma Operating
         Cash Flow determined as of the relevant Exchange Date.

                  4. Section 2.9(a). Section 2.9(a) of the Credit Agreement is
         hereby deleted in its entirety and replaced with the reference
         "[INTENTIONALLY OMITTED]."

                  5. Section 7.2(g). Section 7.2(g) of the Credit Agreement is
         hereby amended by changing the words "90 days" contained therein to the
         words "120 days."

                  6. Section 7.2(j). Clause (ii) of Section 7.2(j) of the Credit
         Agreement is hereby amended and restated in its entirety as follows:

                  "(ii) except in the case of the Senior Notes, 100% of the Net
                  Cash Proceeds thereof (other than any such Net Cash Proceeds
                  that are applied to refinance other Indebtedness of Holdings
                  to the extent permitted by Section 7.8) shall be used by
                  Charter Holdings to make Investments in one or more of its
                  operating Affiliates"

                  7. Section 7.4. Section 7.4 of the Credit Agreement is hereby
         amended by adding the following new paragraph (f) to the end thereof:

                  "(f) so long as no Default of Event of Default has occurred or
                  is continuing or would result therefrom, Charter Holdings may
                  be merged or consolidated with any Affiliate of Paul G. Allen
                  (provided that either (i) Charter Holdings is the continuing
                  or surviving entity or (ii) if Charter Holdings is not the
                  continuing or surviving entity, such continuing or surviving
                  entity assumes the obligations of Charter Holdings under the
                  Loan Documents to which it is a party pursuant to an
                  instrument in form and substance reasonably satisfactory to
                  the Administrative Agents and, in connection therewith, the
                  Administrative Agents shall receive such legal opinions,
                  certificates and other documents as they may reasonably
                  request)"


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                  8. Section 7.5(e). The second parenthetical contained in
         Section 7.5(e) of the Credit Agreement is hereby amended and restated
         in its entirety as follows:

                  "(it being understood that Exchange Excess Amounts (other than
                  Excluded Exchange Excess Amounts) shall be deemed to
                  constitute usage of availability in respect of Dispositions
                  pursuant to this Section 7.5(e))"

                  9. Section 7.5(f). Section 7.5(f) of the Credit Agreement is
         hereby amended and restated in its entirety as follows:

                  "(f) any Exchange by the Borrower and its Subsidiaries;
                  provided that (i) on the date of such Exchange, no Default or
                  Event of Default shall have occurred and be continuing or
                  would result therefrom; (ii) in the event that the Annualized
                  Asset Cash Flow Amount attributable to the assets being
                  Exchanged exceeds the annualized asset cash flow amount
                  (determined in a manner comparable to the manner in which
                  Annualized Asset Cash Flow Amounts are determined hereunder)
                  of the assets received in connection with such Exchange (such
                  excess amount, an "Exchange Excess Amount"), then, unless such
                  Exchange Excess Amount is an Excluded Exchange Excess Amount,
                  the Disposition of such Exchange Excess Amount is permitted by
                  clauses (ii) and (iii) of Section 7.5(e); and (iii) the Net
                  Cash Proceeds of such Exchange, if any, shall be applied to
                  prepay the Term Loans to the extent required by Section
                  2.9(b)"

                  10. Section 7.6(c). Clause (ii) of Section 7.6(c) of the
         Credit Agreement is hereby amended and restated in its entirety as
         follows:

                  "(ii) the Borrower may make distributions to Charter Holdings
                  as described in the last sentence of Section 7.9"

                  11. Section 7.6(d). Section 7.6(d) of the Credit Agreement is
         hereby amended and restated in its entirety as follows:

                  "(d) the Borrower may make distributions to Charter Holdings
                  to permit Charter Holdings (or any parent company thereof) to
                  pay (i) attorneys' fees, investment banking fees, accountants'
                  fees, underwriting discounts and commissions and other
                  customary fees and expenses actually incurred in connection
                  with any issuance, sale or incurrence by Charter Holdings (or
                  any such parent company) of Equity Interests or Indebtedness
                  (other than any such amounts customarily paid out of the
                  proceeds of transactions of such type), provided, that such
                  amounts shall be allocated in an appropriate manner
                  (determined after consultation with the Administrative Agents)


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                  among the Borrower and the other operating Subsidiaries, if
                  any, of the issuer or obligor in respect of such Equity
                  Interests or Indebtedness, (ii) costs and expenses incurred in
                  connection with the Exchange Offers (as defined in the Senior
                  Note Indenture) and (iii) other administrative expenses
                  (including legal, accounting, other professional fees and
                  costs, printing and other such fees and expenses) incurred in
                  the ordinary course of business, in an aggregate amount in the
                  case of this clause (iii) not to exceed $2,000,000 in any
                  fiscal year"

                  12. Section 7.7(f). Clause (ii) of Section 7.7(f) of the
         Credit Agreement is hereby amended by adding the following words after
         the words "Paul Allen Contributions" in the parenthetical contained
         therein:

                  "and Consideration consisting of operating assets transferred
                  in connection with Exchanges"

                  13. Section 7.7(h). Section 7.7(h) of the Credit Agreement is
         hereby amended by changing the amount "$100,000,000" contained therein
         to the amount "$300,000,000".

                  14. Section 7.9. Section 7.9 of the Credit Agreement is hereby
         amended by adding the following sentence to the end thereof:

                  "Notwithstanding anything to the contrary in this Section 7.9,
                  so long as no Default or Event of Default shall have occurred
                  and be continuing, the Borrower shall be permitted to pay
                  (either directly or by way of distribution to Charter
                  Holdings) amounts not in excess of 1.0% of the aggregate
                  enterprise value of Investments permitted hereby (excluding
                  the Marcus Combination) to certain members of the Charter
                  Group."

                  15. Section 7.14(b). Section 7.14(b) of the Credit Agreement
         is hereby amended and restated in its entirety as follows:

                  "(b) In the case of Charter Holdings and the Borrower, (i)
                  conduct, transact or otherwise engage in, or commit to
                  conduct, transact or otherwise engage in, any business or
                  operations other than those incidental to its ownership of the
                  Equity Interests of other Persons or (ii) own, lease, manage
                  or otherwise operate any properties or assets other than
                  Equity Interests of other Persons"

                  16. Section 8(j). Section 8(j) of the Credit Agreement is
         hereby amended and restated in its entirety as follows:


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                  "(j)(i) the Paul Allen Group shall cease to have the power,
                  directly or indirectly, to vote or direct the voting of Equity
                  Interests having at least 51% (determined on a fully diluted
                  basis) of the ordinary voting power for the management of
                  Charter; (ii) the Paul Allen Group shall cease to own of
                  record and beneficially, directly or indirectly, Equity
                  Interests of Charter representing at least 51% (determined on
                  a fully diluted basis) of the economic interests therein
                  (provided that such percentage shall be reduced to 25% after
                  the consummation of an Initial Public Offering); (iii) a
                  Specified Change in Control shall occur; or (iv) the Borrower
                  shall cease to be a direct Wholly Owned Subsidiary of
                  Holdings"

                  17. Section 8(k). Section 8(k) of the Credit Agreement is
         hereby deleted in its entirety and replaced with the reference
         "[INTENTIONALLY OMITTED]".

         SECTION II.       MISCELLANEOUS.

                  1. No Change. Except as expressly provided herein, no term or
         provision of the Credit Agreement shall be amended, modified or
         supplemented, and each term and provision of the Credit Agreement shall
         remain in full force and effect.

                  2. Effectiveness. This First Amendment shall become effective
         as of the date hereof upon receipt by the Administrative Agents of (a)
         counterparts hereof duly executed by Holdings and the Borrower and (b)
         consent letters authorizing the Administrative Agents to enter into
         this First Amendment from the Required Lenders, provided, that the
         amendment described in paragraph 4 of Section I of this First Amendment
         shall not become effective until consent letters authorizing the
         Administrative Agents to enter into this First Amendment have been
         received from the Required Prepayment Lenders.

                  3. Counterparts. This First Amendment may be executed by the
         parties hereto in any number of separate counterparts, and all of said
         counterparts taken together shall be deemed to constitute one and the
         same instrument.

                  4. GOVERNING LAW. THIS FIRST AMENDMENT AND THE RIGHTS AND
         OBLIGATIONS OF THE PARTIES UNDER THIS FIRST AMENDMENT SHALL BE GOVERNED
         BY, AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAW OF THE
         STATE OF NEW YORK.


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         IN WITNESS WHEREOF, the parties hereto have caused this First Amendment
to be duly executed and delivered as of the day and year first above written.

                                   CHARTER COMMUNICATIONS HOLDINGS LLC


                                   By: /s/ Eloise A. Engman
                                       _______________________________________
                                         Name: Eloise A. Engman
                                         Title: Vice President

                                   CHARTER COMMUNICATIONS OPERATING, LLC


                                   By: /s/ Eloise A. Engman
                                       _______________________________________
                                         Name: Eloise A. Engman
                                         Title: Vice President

                                   THE CHASE MANHATTAN BANK,
                                      as an Administrative Agent


                                   By: /s/ Edmund DeForest
                                       _______________________________________
                                         Name: Edmund DeForest
                                         Title: Vice President

                                   NATIONSBANK, N.A., as an Administrative Agent


                                   By: /s/ A. Cacheria
                                       _______________________________________
                                         Name: A. Cacheria
                                         Title: M/D


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