• Historic Shot of Canal Boat on the Canal

    Chesapeake & Ohio Canal

    National Historical Park DC,MD,WV

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  • NEW Overnight parking system

    Before parking a vehicle overnight in any Canal Parking area, visitors must register their vehicle through the new online registration system. Print your reciept and place on your dashboard. If unable to print, please visit the nearest visitor center. More »

  • Water Pump Handles Temporarily Removed

    Water pump handles at Bald Eagle Island and Huckleberry Hill Hiker Biker Campsites have been removed due to bad water samples. Handles will be reinstalled when good water samples are received.

  • Boat Tours at Great Falls

    Due to low water levels in the Great Falls area, call the Great Falls Tavern Visitor Center (301-767-3714) in advance of your trip to confirm the mule-drawn boat tour schedule.

  • Parking Lot Closure

    CSX is now beginning a phase of their bridge project that requires the closure of the Lock 74 parking lot for approximatly 18 months. Access to visitor parking near Lock 75 is now re-opened with a gravel parking lot at the site.

How a Lock Works

A lock is an elevator for boats. It lifts boats up or down to the next level on the canal. There are 74 locks on the C and O Canal. Only one boat at a time can fit in the lock. Locks are 100 feet long and 15 feet wide. This leaves only six inches on each side and one foot at each end of the boat when it is inside the lock.

Watch a video showing a boat locking through

Unhitching the mules at the lock

Unhitching the mules  at the lock

After the mules are unhitched from the boat the boat enters the lock.

boat being guided into lock

Boat being guided into the lock

Using the ropes attached to the boat, Lock Keepers guide the boat into the lock. This prevents the boat from hitting the lock walls and causing damage.

boat in lock lowered

The lock keeper closes the gates. The canal boat is totally enclosed in the lock. The water is either lowered or raised depending on which direction the boat is travelling.

wicket closeup

Close up of the open wickets with water passing through

A lock key is used to open the wickets. Wickets are paddles in the bottom of the gate that allow water through.

boat leaving lock

Boat exiting lock


When the boat reaches the correct level, the lock gates are opened and the boat exits the lock. It takes about 10 minutes for the boat to "lock through".

Did You Know?

Photo Potowmack Company canal lock at Great Falls Virginia.

George Washington's dream of connecting the eastern states with the western frontier led to the creation of the Patowmack Company. Canals were built around unnavigable parts of the Potomac River for improved commerce. The C&O Canal inherited the right of way after the Patowmack Company's demise. More...