From Bulbapedia, the community-driven Pokémon encyclopedia.
Frost Cave was part of the Articuno Island (AKA Prussian Town Pokémon Network), the former hostee of Bulbagarden. It was one of the leading Pokémon fan websites of its time. The site was started and maintained by a user named Dragonice. After Dragonice left Frost Cave on October 15, 2000, the site was no longer maintained. Its lifespan was approximately a year and a half.
Dragonice's farewell statement
The main evidence remaining of the website is Dragonice's farewell statement, which can be here (the second post down). In his farewell, Dragonice announced that he will no longer be maintaining the website, initially claiming that he "doesn't have time" to run the website. Then, he cited the Pokémon Company's decreased popularity, before finally going into an all-out attack on the current state of the Pokémon community, saying that he is "absolutely disgusted". He criticized the webmasters of Pokémon fan-sites for only seeking to make a profit and have their website get several hits. He believed this priority took away what made Pokémon fan-sites fun.
However, he ended the statement on a much more positive note, discussing a variety of positive aspects of the Pokémon community, such as fan-sites like Pokémon Forest X. He then thanked a vast number of people, and said that he will continue to be working with Bulbagarden and Articuno Island.