Its walls studded with crystal "daggers," the 400-foot-deep (120-meter-deep) Cave of Swords is closer to the surface than the Cave of Crystals.

While there are more crystals in the Cave of Swords, they are far smaller, typically about a yard (a meter) long. Their relative compactness is likely due to a rapid temperature decline, as opposed to the far more gradual change that is believed to have encouraged the megacrystals in the deeper cave.

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