DC -- Library of Congress -- Tunnels:
[1] LOCTUN_181227_01.JPG
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[2] LOCTUN_181227_05.JPG
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[3] LOCTUN_181227_08.JPG
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[4] LOCTUN_181227_11.JPG
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[5] LOCTUN_181227_14.JPG
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[6] LOCTUN_181227_16.JPG
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[7] LOCTUN_181227_23.JPG
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[8] LOCTUN_181227_26.JPG
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[9] LOCTUN_181227_29.JPG
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[10] LOCTUN_181227_32.JPG
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[11] LOCTUN_181227_35.JPG
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[12] LOCTUN_181227_39.JPG
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[13] LOCTUN_181227_41.JPG
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[14] LOCTUN_181227_43.JPG
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[15] LOCTUN_181227_46.JPG
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[16] LOCTUN_181227_49.JPG
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[17] LOCTUN_181227_51.JPG
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