Tunnelers' Dream

{
  "biome": "minecraft:windswept_hills",
  "lakes": false,
  "features": true,
  "decoration": false,
  "layers": [
    {
      "block": "minecraft:bedrock",
      "height": 1
    },
    {
      "block": "minecraft:stone",
      "height": 230
    },
    {
      "block": "minecraft:dirt",
      "height": 5
    },
    {
      "block": "minecraft:grass_block",
      "height": 1
    }
  ],
  "structure_overrides": ["minecraft:mineshafts", "minecraft:strongholds"]
}