Traditional evacuation training is ineffective as it does not simulate decision making against tough disaster situations. Therefore, evacuation training should be significantly enhanced to offer realistic simulated evacuation experiences, entailing decision making. A promising approach to the enhancement is to introduce virtual reality (VR) into evacuation training, and there have been numerous VR-based evacuation training systems. The authors launched the project Evacuation Training in Metaverse (ETM) considering the recent surge of interest in the metaverse as a VR extension. The ETM system is being developed based on the design principle: gathering numerous participants, pursuing high fidelity, and simulating a sudden earthquake. The ETM system transforms ordinary time to emergency time by creating a sudden earthquake, allowing participants to experience simulated earthquake evacuation in a high fidelity virtual world developed from an open-city model, photogrammetry, etc. The participants make decisions in the virtual world while being influenced by numerous others.