The Tappan Zee is a wide, open section of the Hudson River, approximately three miles across, located just north of New York City. It is a saltwater tidal basin connecting Westchester and Rockland Counties, spanned by the Tappan Zee Bridge. The paddling experience here is defined by significant marine influences, including strong tidal currents and exposure to wind and boat traffic. The river can be intimidating due to its width and the presence of large commercial vessels like tankers, tugboats pushing barges, and ferries, which create substantial wakes. Conditions vary greatly; the water can be choppy and rough, especially when stirred by boat traffic or wind, but can also be exceptionally calm, resembling a mountain lake, particularly on weekend mornings or evenings.

Several public access points serve paddlers on both sides of the river. On the eastern shore in Westchester County, key launches include Kingsland Point Park in Sleepy Hollow, the Kathryn W. Davis Riverwalk Center, Losee Park in Tarrytown, and Pierson Park in Tarrytown. On the western shore in Rockland County, Memorial Park in Nyack is a common put-in and take-out. From these points, paddlers can explore the shoreline, pass the historic 1883 Tarrytown Lighthouse, and venture into sheltered areas like the Pocantico River, accessible near high tide, or the Piermont Marsh and Sparkill Creek on the western side, which offer some protection from waves. A popular and challenging route for experienced kayakers is the open-water crossing of the Tappan Zee itself, such as the 2.7-mile paddle from Losee Park in Tarrytown to Memorial Park in Nyack, a round trip of about five miles.

Tidal planning is essential. The Hudson River experiences pronounced tidal currents here, with an ebb (outgoing) and flood (incoming) cycle. Paddlers report strong outgoing tides and note that currents can reach one to one and a half knots. Timing a crossing to coincide with slack tide or to have a favorable current is crucial, as paddling against the tide significantly increases effort and time. Wind is another major factor, typically coming from the southwest, and can create a fetch across the three-mile width, building waves that combine with boat wakes to create challenging, confused seas. The water temperature follows seasonal patterns, with examples like 59°F recorded in early May. The area is active with paddling clubs and guided tours, primarily from spring through fall, offering instruction and group trips, sometimes with safety boat support. Participants should be prepared for variable conditions, possess appropriate endurance, and always wear a personal flotation device.