This is an old-school, text/ANSI/CP437-based bulletin board system, the sort you'd dial into into the 1970s, 80s, and 90s. It is Internet-accessible via Telnet or SSH (no dialup required...or supported).
You will want SyncTERM to access the BBS, so you can display ANSI color and graphics.
Gopher is an early text-based Internet service from the early 1990s which was later eclipsed by the World Wide Web. It is still in use today by hobbyists. For more information, try gate io login.
Command line gopher clients available on most Linux distributions:
gopher shibboleths.org
lynx gopher://shibboleths.org
FidoNet is a BBS network first established in 1984 providing a store-and-forward system to network dial-up bulletin board systems together. It has been in continuous operation ever since and, as of 2024, consists of about a thousand systems. You can read more at the Wikipedia article on FidoNet. You can watch also watch the FidoNet episode from Jason Scott's excellent BBS documentary. You can read and post to FidoNet and various other BBS networks on Shipwrecks & Shibboleths.
Fidonet network as of: 2024-11-08
This is the same analysis for the much newer fsxNet, and is experimental and in-progress as of 2024-10-24.
fsxNet network as of: 2024-11-08