
The Rat Hole was a 2-lane tunnel constructed in 1927 and traversed north-south under present day 109th Street between 104th and 105th Avenue, in the northwest corner of Downtown, in Edmonton, Alberta, Canada. It was 168 metres in length, 3.3 metres in height, and constructed to accommodate automobile, bicycle and pedestrian traffic. The City of Ed...
Found on
http://en.wikipedia.org/wiki/Rat_Hole

Rat-hole is American slang for a hide or store, especially one for money.
Found on
http://www.probertencyclopaedia.com/browse/ZR.HTM
No exact match found.