We are approaching one of the Grand Canal locks. The locks on this canal are 14 feet wide, allowing some good sized boats to enter. This lock raises/lowers the boat about 8 feet. The canal depth is 3-4 feet. Most of the locks on the canals, other than the Grand or Regents, are only 7 feet wide. The famous narrow-boats are all 6 foot 8 inches wide, and up to 65 feet long. I'm not sure I would want to put a 65 foot boat in a lock with only 2 inches clearance on each side!
Entering the lock, we tie the boat loosely to the side.
Bill is closing the lower gate, with instruction from Jenny. These counter-balanced lower arms are the same as the upstream arms you can see on the picture just above. On these double wide locks, you close one gate, then walk to the other end of the lock, and cross on the gate arms, then close the other arm. Next step is to take your winch handle (you get one with the permit to use the canals) and crank up the underwater valve on the upstream gate.
The lock fills, you open the top gate, and motor away! Whole thing takes about 20-30 minutes. I've seen pictures of a hillside series of over 10 locks up north. Must take most of a day to traverse that hill.
This lock, which we just traversed is one of the most famous ones. It is in the center of Camden market, which is listed as the third most visited place in London--lots of folks watching to see If I was going to fall in.
We had noticed narrow sets of stairs going down from the tow path into the water of the canal. We thought they might be to leave the boats if the water level was down, but found out that they were for horse recovery!! When the canals were first built, the boats and barges were pulled by a single horse walking along the narrow tow path. Occasionally something would startle the horse, and it would fall into the canal. The boatman could walk his semi-submerged horse to the next stairway, and lead him out.