The Country Mouse has never really been around large bodies of water. Technically, the Mississippi River is a long body of water, but it wasn't really that close to Qulin. Of course, City Mouse grew up just hours from the Atlantic Ocean and on Lake Watauga, Tennessee, so he's practically a water baby. But when the Garretts moved to upstate New York, there was something else new to check out: the state's system of locks and dams.
If you think anything like Heather, your first thought of the word 'lock' was a reference to Lost. Turns out, it's this crazy system of water channels that helps boats move up and down rivers. (Them Yankees think of everything!) The lock raises and lowers boats between stretches of water of different levels on river and canal waterways. Wikipedia told us that the distinguishing feature of a lock is a fixed chamber in which the water level can be varied; whereas in a caisson lock, a boat lift, or on a canal inclined plane, it is the chamber itself (usually then called a caisson) that rises and falls. Locks are used to make a river more easily navigable, or to allow a canal to take a reasonably direct line across land that is not level.
Since Albany is located on the north end of the navigable Hudson River it's been a hub of transportation since the late 1700's. In fact, the first steamboat service connected Albany and New York City! It's also home to the eastern terminus of the Erie Canal...and it's all possible because of these lock things!