Exhibit 6.47Exhibit
10.47

March 25, 2004

Robert M. MacTarnahanScott
MacTarnahan MacTarnahan Limited
Partnership11416 SW Lynnridge AvenuePortland, Oregon 97225

Re: Agreement to Provide
Credit Accommodation on behalf of Portland Brewing Company (the "Company")

Dear Mac and Scott:

In
connection with the Companys existing line of credit with Washington Mutual Bank
(WAMU), WAMU has requested additional collateral in the form of a pledged
savings account in the amount of $400,000. MacTarnahan Limited Partnership
(MacTarnahan) has agreed to pledge the savings account and to provide
this credit accommodation subject to the terms and conditions of this letter. The parties
agree as follows:

1.    Amount
and Type of Collateral; Term. MacTarnahan will pledge a savings           account in
the amount of $400,000 (Additional Collateral) to           WAMU on
behalf of the Company as additional collateral to the Companys           existing
credit line with WAMU beginning on March __, 2004 until the earlier of           (a) the
WAMU loan is paid off and the Additional Collateral is released; or           (b) the
Company defaults in its obligations under Section 3 or 5 hereof,           (c) WAMU,
the Company and MacTarnahan agree that that the Additional           Collateral may be
released or the amount reduced, or           (d) Closing occurs under
that certain Asset Purchase Agreement           between the Company, as seller, and
Pyramid Breweries Inc. and PBC Acquisition           LLC, as buyer, dated January 26,
2004.

2.    Collateral
Fee.For the credit accommodation, the Company will pay to           MacTarnahan (a) a
collateral fee equal to 3.5% simple interest per annum on           the Additional
Collateral amount, which amount shall (i) increase to 12% if           for any
reason WAMU has not released the Additional Collateral by the date on           which the
Closing occurs under the acquisition agreement and (ii) be due           and payable
in full when the Additional Collateral is released from the WAMU           pledge (unless
accelerated as provided in Section 3) plus (b) interest on           any portion of
the Additional Collateral drawn by WAMU, calculated at the rate           of 12% per
annum on the amount drawn until the same has been reimbursed in           accordance with
Section 3, which amount shall be due and payable monthly, in           arrears, on the
last day of each month.

3.    Reimbursement
Obligation.In the event that the Additional Collateral or           any portion
thereof is drawn on by WAMU, the Company will pay and reimburse           MacTarnahan, on
demand, (a) the amount drawn down, plus (b) the           collateral fee
accrued under Section 2(a), above, to the date such payment and           reimbursement
is made by the Company to MacTarnahan, plus (c) any other           amounts due
under this letter agreement.

4.    Security
Interest.The Company has previously granted MacTarnahan under a           Security
Agreement dated November 1, 2001, a lien and security interest in           certain
assets of the Company, as more particularly provided therein (including           all
amendments thereto and modifications thereof through the date of this
          Agreement, the Security Agreement). The obligations of the Company
          under this letter agreement including, without limitation, the payment
          obligations under Section 2, 3 and 5 hereof, shall be secured by the
          Collateral, as

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defined in the Security Agreement,
and the Security           Agreement is hereby amended to include such obligations among
the obligations           secured thereby.

5.    Loan
Costs.The Company will pay when due, or will reimburse to           MacTarnahan on
demand, all of MacTarnahans costs in originating and           administering this
credit accommodation, and in creating and/or perfecting the           security therefor,
including legal fees, filing fees and similar costs.

Please
countersign this letter agreement to evidence the Companys and the MacTarnahan
Limited Partnerships agreement with the terms outlined above.

Very Truly Yours,

Portland Brewing Company

/s/ FREDERICK BOWMANName: Frederick Bowman
Title: President

Acknowledged:

MacTarnahan Limited
Partnership

By: Harmer Mill &
Logging Supply Co.Its: General Partner

/s/ ROBERT M. MACTARNAHANBy: Robert M. MacTarnahan
Its: President