Great Northern Engineering Drawing: Cascade Tunnel, Washington, prepared in 1956. Burlington Northern File Number 9531, Reference Number 10104.

Great Northern Engineering Drawing: Cascade Tunnel, Washington, prepared in 1956. Burlington Northern File Number 9531, Reference Number 10101.

Great Northern Engineering Drawing: Cascade Tunnel, Washington, prepared in 1956. Burlington Northern File Number 9531, Reference Number 10101.

Great Northern Engineering Drawing: Cascade Tunnel, Washington, prepared in 1956. Burlington Northern File Number 9531, Reference Number 10102.

Great Northern Engineering Drawing: Cascade Tunnel, Washington, prepared in 1956. Burlington Northern File Number 9531, Reference Number 10104.

Great Northern Engineering Drawing: Cascade Tunnel, Washington, prepared in 1956. Burlington Northern File Number 9531, Reference Number 10107, Sheet 004.

Great Northern Engineering Drawing: Cascade Tunnel, Washington, prepared in 1956. Burlington Northern File Number 9531, Reference Number 10105, Sheet 002.

Great Northern Engineering Drawing: Cascade Tunnel, Washington, prepared in 1956. Burlington Northern File Number 9531, Reference Number 10105.

Great Northern Engineering Drawing: Cascade Tunnel, Washington, prepared in 1956. Burlington Northern File Number 9531, Reference Number 10107.

Great Northern Engineering Drawing: Cascade Tunnel, Washington, prepared in 1956. Burlington Northern File Number 9531, Reference Number 10105, Sheet 003.