The Saint Lawrence River fractures into 1,864 islands between Kingston and Brockville, creating a maritime labyrinth where granite outcrops support gilded-age summer estates, stone castles, and thousand-year-old pines. The archipelago served as a contested boundary during the War of 1812, with British and American forces fortifying opposing islands. By the 1870s, American industrialists discovered the waterway, commissioning architects to build Rhineland-inspired castles on private islands. George Boldt's six-storey Rhineland fortress on Heart Island remains the region's most photographed structure, abandoned unfinished in 1904 after his wife's death. Today, 1000 islands cruise tickets price tours operate from three departure ports. Kingston departures follow the Canadian channel past Fort Henry and the Admiralty Islands. Ivy Lea departures navigate the international span, passing beneath the Thousand Islands Bridge. Gananoque departures access the densest island cluster, where nineteenth-century boathouses and contemporary glass mansions occupy adjacent shorelines. Standard sightseeing cruises last ninety minutes and traverse twelve to fifteen nautical miles. Extended routes with Boldt Castle stops add two hours for island exploration. Sunset departures depart at 18:30 from May through September, when the granite faces catch horizontal light. The waterway's ecology supports endemic fish species and migratory bird corridors. Glacial retreat fifteen thousand years ago left the Frontenac Arch exposed, creating the only land bridge connecting the Canadian Shield to the Adirondack Mountains. The rock substrate prevents agricultural development, preserving pre-settlement forest cover across the island interiors. Parks Canada and the U.S. National Park Service jointly manage cross-border protected areas, maintaining navigation channels and historic structures. Cruise operators hold commercial permits limiting vessel size and wake height to protect shoreline nesting sites and wooden docks built in the 1920s.