At which 1997 event were Pokémon Gold and Silver first publicly showcased?

Pokémon Gold and Silver were first publicly showcased at Nintendo Space World 1997.

The event took place in Japan from November 21 to 24, 1997. Nintendo presented an early prototype of the sequels, which attracted substantial attention as the next major Pokémon games. The demonstration showed that the follow-up would expand beyond a simple update to Red and Blue.

Gold and Silver eventually introduced a new region, new Pokémon species, breeding, held items, the Pokégear, a real-time clock, and compatibility with earlier games. The final games changed considerably from the Space World prototype, and several displayed creatures never appeared in the finished releases.

Nintendo Space World was a Nintendo-focused exhibition rather than the Tokyo Game Show or E3. The 1997 showcase is especially notable because it offered fans an early look at Johto and the franchise's second generation.