concretesubmarine.com/ FORUM

I guess the name itself implies that it’s a place where you can find stuff that is not available on other platforms. Most of the time because it is illegal. The core idea was of creating a computer network with restricted access that is used chiefly for illegal peer-to-peer file sharing. You can find certain services or products that you will struggle to find on the “regular internet” or even offline. You can try https://darkcatalog.com/nemesis-market/ and see what this is about. Accessing the dark web is not illegal.