What year was Niagara Cave officially opened to the public?

Niagara Cave officially opened to the public in 1935. This date is significant as it marked the beginning of public access to one of Minnesota's most unique natural attractions, allowing visitors to explore the stunning underground formations, including stalactites and stalagmites, that had been formed over thousands of years. The opening of the cave in 1935 also aligned with a growing interest in natural wonders during that period, as more people sought to engage with and experience the beauty of the natural world firsthand. The other years listed do not correspond to the official opening date, as they precede the establishment of the cave as a public attraction.