Mile 42.2 - Ahh, the jewel of the Canal! At 516 feet and with 7 arches, this is the longest of all 11 of the canal's aqueducts. It is currently supported with the aid of steel beams (flood damage of course) but a restoration project has been announced by the park service.
A description of the aqueduct from Yahoo!
Aerial view of the aqueduct.
It's difficult to read but at the center of the aqueduct is a commemorative plaque with the names of those who worked this project.
This winter picture show the piles of sticks and mounds of floatsam that accumulates at the base of each aqueduct pillar. These are locked in ice and therefore a bit worse than usual but all the aqueducts have this problem.
The supports which were installed after Hurricane Agnes (1972) wrap themselves around the outside and hold it together. There are horizontal rods that go through the top and the bottom joined to vertical iron beams. These squeeze the aqueduct while supports inside the basin push out to keep the fragile walls intact.
The stone for the Monocacy Aqueduct was quarried from nearby Sugarloaf Mountain. In Colonial times, sugar was sold in "loaves", cylindrical mounds with rounded tops, hence the name. The top of this mountain is 1,280 feet and there are a number of hiking trails through it, ranging from 1 to 8 miles in length. See the MAPS sections for a trail map.
Climbing on Sugarloaf.