Welcome Aboard!
You are not logged in.
From Wikipedia: Seneca Aqueduct — or Aqueduct No. 1 — is a naviduct that carries the Chesapeake and Ohio Canal (C&O) over Seneca Creek in Montgomery County, Maryland. The C&O built eleven aqueducts along its 184.5 miles (296.9 km) length. Seneca Aqueduct is a unique structure, not only being the first built, but also the only red sandstone aqueduct on the C&O?and the only aqueduct that is also a lock (Lock 24, or Riley's Lock). It is located at the end of Riley's Lock Road in Seneca, Maryland. 
Only two of these exist in the world? Where is the other one?
Offline
Netherlands
Capt Mike
Offline
For the win!
Offline
Now that is a cool picture.
Offline
darbrewe wrote:
Now that is a cool picture.
I thought the same.
Got that from National Park Service.
Offline