The Eden Project is marking its 25th anniversary this year, a milestone that lands with real weight in Cornwall and far beyond it. Since opening in 2001, the site near St Austell has welcomed more than 25 million people through its gates.

That scale matters because the Eden Project was not built in an ordinary setting. It rose from a once-exhausted clay pit near St Austell and has become one of Cornwall's most iconic landmarks, a place that mixes environmental ambition with visitor appeal. The site now includes the Biomes, outdoor gardens, Nature's Playground, Invisible Worlds and the Seed sculpture in the Core building.

The biggest draw remains the Rainforest Biome, the largest on the site. It measures 100 metres wide and 55 metres high, and inside it more than 1,000 varieties of rainforest plants grow in conditions where temperatures can climb to 37C. The Mediterranean Biome houses more than 1,000 species, while Invisible Worlds uses immersive digital technology to reveal hidden systems that connect life on Earth.

That mix of spectacle and science is what has kept the site relevant long after its opening year. Visitors still come for the scale of the Biomes and the visual impact of the Seed sculpture, and co-founder Tim Smit is often photographed near that giant form in the Core building.

The anniversary also underlines a simple fact: the Eden Project is no longer just a bold idea from 2001. It is an established part of Cornwall's landscape, and the numbers show it has stayed that way by giving people more than a single attraction to see. It offers heat, humidity, digital immersion and open-air gardens in one place, and that breadth is why the milestone feels less like a ceremony than a measure of endurance.