Elliott Bay's commercial maritime traffic peaks at 1,100 vessel movements per month, yet the water between Pier 55 and Alki Point clears each evening for a parade of sailboats and touring craft that trace the city's oldest recreational corridor. Seattle's sunset cruise tradition began in 1949 when Argosy Cruises launched its first harbor loop, a 90-minute circuit designed to showcase the Port of Seattle's grain terminals and container yards to tourists who had never seen deep-water industrial infrastructure up close. The route has changed little in seven decades. Today, sunset cruise party Seattle departures occupy the same pier that once served Alaska-bound steamships, and the vessels — ranging from 65-foot sailing yachts to 150-passenger motor cruises — share the channel with container ships bound for Tacoma and tugboats guiding barges toward the Ballard Locks. The Olympic Mountains form the western horizon, their peaks holding daylight 20 minutes longer than the waterfront below. On clear evenings between May and September, the sun sets directly behind Bainbridge Island, casting the ferry terminal and Smith Cove into silhouette. Photographers favor the stretch between Pier 66 and the Great Wheel, where the skyline compresses into a single frame. The harbor itself is a working waterfront, not a marina district. Cranes at Terminal 46 swing containers through the golden hour, and the Washington State Ferries maintain their 20-minute Bainbridge schedule without pause. Seattle harbor cruises navigate between these rhythms, threading the gap between the ferry lanes and the cargo anchorage. Most sailing tours hug the eastern shore, passing the Seattle Aquarium, the piers of the Central Waterfront, and the industrial finger docks south of Safeco Field. Narrated cruises highlight the city's geography — the glacially carved trough of Puget Sound, the 1917 construction of Harbor Island, the fill projects that extended downtown into tide flats. Elliott Bay's water temperature holds at 50°F year-round, a function of the Sound's 600-foot depth and its exchange with the Strait of Juan de Fuca. The bay's surface is rarely flat; prevailing southwest winds produce a two-foot chop most afternoons, subsiding only after 7 p.m. when the land breeze reverses. This thermal shift — cool air draining from the Cascades — is what clears the evening haze and sharpens the horizon, a pattern that sailing schedules have long relied upon. The light lasts until 9:30 p.m. in midsummer, compressing the golden hour into a 40-minute window that begins as the ferries switch on their deck lights.