Checked content

File:CPRR Donner Summit Tunnel Hand Drilled Granite 1868.jpg


Composite illustration of hand drilling marks on the granite walls inside of CPRR Tunnel #6 (the "Summit Tunnel") and a piece of granite removed from the tunnel after blasting with a drill mark.

Both digital photographs and composite illustration by the uploader ( Centpacrr). Drilled granite sample in uploader's collection, "The Cooper Collection of US Railroadiana".


I, the copyright holder of this work, hereby publish it under the following licenses:
You may select the license of your choice.
The following pages on Schools Wikipedia link to this image (list may be incomplete):


I want to learn more...

Wikipedia for Schools is designed to make learning fun and easy. SOS Children's Villages helps more than 2 million people across 133 countries around the world. Why not try to learn more about child sponsorship?