The Lost Cities

Overview

The Lost Cities is a world generation mod that replaces Minecraft's standard terrain with massive, procedurally generated abandoned cities. These aren't small structures scattered across the landscape; they are entire urban environments spanning hundreds of chunks, complete with multi-story buildings, underground subway networks, elevated highways, bridges, fountains, and parks. The mod uses vanilla Minecraft blocks for all construction, meaning it doesn't add any new items, blocks, or entities to the game.

What makes the mod compelling is the sheer variety of generation styles available. You can play in a standard post-apocalyptic cityscape with explosion damage and ruins, explore ancient jungle cities overgrown with Vines and Leaves, survive in floating glass bubble cities suspended in void, or navigate drowned Atlantis-style cities with raised water levels. The mod also adds its own dimension (ID 111 by default) that generates a dedicated Lost City world you can travel to separately from the Overworld.

Since this is purely a world generation mod, you can browse any recipes or items from your other installed mods using the tabs on this page. The Lost Cities itself focuses entirely on reshaping the world around you.

World Generation Profiles

The Lost Cities includes 16 selectable world profiles, each creating a dramatically different experience. Profiles control everything from city density and building height to explosion damage, ruin levels, foliage overgrowth, and whether vanilla structures like Villages and Strongholds still generate. You select a profile when creating a new world, and it cannot be changed afterward.

Standard Profiles

The Default profile generates cities with a 2% spawn chance per chunk, buildings up to 9 floors tall with up to 4 basement levels, and includes explosion damage, ruins, and a rubble layer. This is the complete Lost Cities experience with all features enabled. The No Damage profile is identical but removes all explosion damage, disables ruins and rubble, and prevents Ravines from generating inside cities. This is ideal if you want intact buildings to explore without navigating destroyed sections.

Rare Cities drops the city chance to 0.2%, making cities a rare discovery in an otherwise normal world. This is the recommended profile for large modpacks where you want cities to be special finds rather than the dominant terrain feature. Ruins are disabled in this profile, and railways can end at city edges rather than requiring connections to other cities.

Only Cities does the opposite: the entire world is urbanized. City chance is set to 20% with a maximum radius of 256 blocks, and biome factors reduce city density slightly in Rivers and Oceans. Tall Buildings pushes buildings to extreme heights with 4-20 floors, larger explosion radii up to 60 blocks, and explosions reaching up to Y=256. This profile is performance-heavy and best suited for powerful hardware.

Themed Profiles

Ancient creates jungle-overgrown cities with 10% Vine coverage, 5% leaf block coverage up to 6 blocks thick, and a 90% ruin chance. Buildings are heavily damaged and covered in vegetation. This profile restricts biomes to Jungle, Jungle Hills, Jungle Edge, and some Ocean and River, so deserts, plains, and mountains won't appear. All explosion damage is disabled.

Wasteland removes all water from the world, disables lake generation, and strips away nearly all foliage. Cities generate at 50% ruin chance in a barren desert landscape restricted to biomes like Desert, Stone Beach, and Wasteland. This works best with Biomes O' Plenty installed for the additional arid biomes. Atlantis raises the water level by lowering the water offset to -20, partially flooding all cities. Buildings stand partially submerged with a 10% ruin chance.

Safe mode disables all Spawners and removes all loot from Chests, but enables interior lighting in buildings. This is essentially a creative exploration mode where you can freely explore the architecture without combat.

Sphere & Landscape Profiles

Four profiles use the Space landscape type, which generates cities inside glass sphere bubbles floating in void or on a secondary landscape. These are the most visually striking and mechanically unique options in the mod.

Space places cities inside glass bubbles floating in empty void. City chance is boosted to 60% with a maximum radius of 90 blocks, and spheres have a 70% generation chance. Each sphere contains a complete city with buildings and streets. No Villages, Strongholds, Mansions, Ocean Monuments, or Mineshafts generate. Railways and highways are disabled, but spheres are connected by Monorails (80% chance per sphere). Interior lighting is enabled since there's no sky light.

Water Bubbles is similar but the area outside spheres is flooded ocean. Spheres sit at a horizon of Y=90 with a water offset of -30, creating underwater glass domes with dry city interiors. The external terrain uses the "water_empty" private profile. All explosion damage is disabled, so the glass domes remain intact.

Biosphere generates jungle-filled glass domes on a barren wasteland exterior. Biomes inside spheres are restricted to Jungle types, while the outside uses the "bio_wasteland" private profile with no water, heavy ruins (100% ruin chance), and minimal vegetation. Spheres have a 40% chance to generate, and mini explosions can damage buildings between Y=60 and Y=75. This profile works best with Biomes O' Plenty.

Floating puts cities on floating islands above a void floor at Y=0. The water offset is pushed to +70 (effectively removing surface water), ground level starts at Y=50, and building cellars are limited to 2. Railways are disabled and highways use a tighter spacing mask of 15. City chance is reduced to 3%, making floating city islands a rarer sight. No vanilla structures generate.

Cavern uses its own landscape type to create a dark underground world similar to the Nether. The horizon is set to Y=128, fog is completely black (RGB 0,0,0), and interior lighting is enabled so buildings glow in the darkness. All explosion damage is disabled and lakes don't generate. This is the most atmospheric profile but is noticeably heavy on performance.

City Structure and Features

Cities in The Lost Cities are built on a chunk-based grid system. Each chunk within a city's radius has a chance to contain a building (30% by default), with the rest being streets, parks, or open areas. Buildings range from ground-level structures to towering skyscrapers depending on the profile's floor settings. The default profile allows 0-9 floors above ground (typically 4-6) and 0-4 basement levels.

Buildings

Standard buildings occupy a single chunk (16x16 blocks) and are constructed from palette-based block sets that vary by biome. Desert cities use Sandstone and Terracotta palettes, while standard cities use Stone, Concrete, and Glass. Special 2x2 buildings spanning four chunks have a 3% chance to generate, and these can be Libraries (10% of 2x2 buildings) or Datacenters (10% of 2x2 buildings). Buildings have a 60% chance for doorways on their sides and a 20% chance for decorative front entrances.

Damage and Decay

The default profile applies two types of destruction to buildings. Large explosions have a 0.2% chance per chunk, creating craters with a 15-35 block radius between Y=75 and Y=90. Mini explosions are more common at 3% chance, with 5-12 block radii between Y=60 and Y=100. These create realistic damage patterns where sections of buildings are blown out, floors are collapsed, and debris is scattered to nearby chunks. The rubble layer adds Dirt and Leaf blocks around the base of damaged structures. Lonely blocks left floating after explosions have a 5% chance to be removed and a 40% chance to be destroyed or displaced.

Streets and Parks

Streets fill the spaces between buildings and use predefined patterns from the asset registry. Fountains have a 5% chance to appear at street intersections, providing decorative water features. Parks are open green spaces that can generate with trees and vegetation depending on the profile's foliage settings. Bridges with a 70% generation chance connect buildings across gaps and between elevated highways.

Transportation Networks

Underground Railway System

The subway system generates on a 20x20 chunk grid, running 3 blocks below ground level. Rail lines run in horizontal and vertical directions and can include straight sections, bends, three-way junctions, and terminus points. Stations appear at regular grid positions (every 5 chunks along the rail line) and come in two varieties: surface stations with open roofs, and underground stations fully enclosed below ground.

The tracks are powered by default, so you can hop in a Minecart and ride between cities without placing additional Powered Rails. The underground tunnels are mostly unlit, making them dangerous but efficient for long-distance travel. Railway tunnels have a 1% chance per chunk of containing a rail dungeon, a small side room with its own loot table containing Diamond Axes, Iron Ingots (3-10), Diamonds (2-9), Emeralds (2-5), and Gold Ingots (1-5).

Highway System

Highways are elevated road structures that run above ground level connecting cities. They generate using Perlin noise with a main scale of 50 and secondary scale of 10, creating organic-looking routes rather than perfectly straight lines. By default, highways require cities on both ends to generate (configurable). The highway distance mask of 7 means highways appear roughly every 8 chunks. Bridges span between highway sections at different heights, creating dramatic elevated crossings.

Monorails (Sphere Profiles Only)

In the Space, Water Bubbles, and Biosphere profiles, city spheres can be connected by Monorails. Each sphere has an 80% chance (configurable) to attempt a Monorail connection in each of the four cardinal directions. Monorails run horizontally and vertically between sphere surfaces, providing transportation between otherwise isolated glass bubble cities.

Loot Tables

The Lost Cities adds two custom loot tables for Chests found throughout the cities and railway system. Each Chest rolls 2-4 items from its loot pool. Keep in mind that 20% of buildings are generated without any loot, and within loot-bearing buildings, 20% of individual Chests are still empty. When running the mod in a modpack, other mods may add to or modify these loot tables.

The Lost Cities Dimension

Beyond modifying Overworld generation, the mod adds a dedicated Lost Cities dimension with ID 111 (configurable). This dimension generates a complete city world using its own profile ("default" by default, configurable via the dimensionProfile setting in lostcities.cfg). The dimension is separate from whatever profile you chose for the Overworld, so you can have rare cities in the Overworld and a fully urbanized dimension accessible via portal.

If Biomes O' Plenty is installed and the dimensionBoP setting is enabled (true by default), the dimension will use BoP biomes for terrain generation. This creates more varied city environments with different block palettes across biome transitions. You can disable the dimension entirely by setting the dimension ID to -1 in the configuration.

City Sphere Mechanics

The Space, Water Bubbles, and Biosphere profiles use a unique City Sphere system where cities generate inside glass bubbles. Each sphere has a randomly determined center position and radius, scaled by the CITYSPHERE_FACTOR (1.2x by default). The sphere's glass shell is constructed from the city style's block palette, and the interior contains a complete miniature city with buildings, streets, and infrastructure.

The landscape outside spheres is controlled by a secondary profile. In the Space profile, outside is pure void. In Water Bubbles, outside is ocean water. In Biosphere, outside is a barren wasteland with occasional heavily ruined cities (0.8% city chance, 100% ruin rate). Surface variation inside and outside spheres can be configured independently, affecting how the terrain within and around the bubbles appears.

Biomes inside spheres can be overridden. The Biosphere profile forces jungle biomes inside all spheres regardless of what biome the world generator would normally place there. Individual spheres can also have predefined biomes set via the predefined sphere system, allowing datapack or config-level control over specific sphere contents.

Configuration

All configuration is done through the lostcities.cfg file in your config directory. Beyond selecting a profile at world creation, every individual setting within a profile can be overridden. The configuration is divided into several categories.

City Generation

CITY_CHANCE controls the probability (0.0-1.0) that a chunk becomes a city center. CITY_MINRADIUS and CITY_MAXRADIUS (default 50 and 128) set the size range of cities in blocks. City level heights determine the ground elevation of different city tiers: Level 0 at Y=75, Level 1 at Y=83, Level 2 at Y=91, and Level 3 at Y=99. Higher-tier city chunks can have taller buildings. The CITY_BIOME_FACTORS setting lets you reduce city generation in specific biomes (for example, "river=0.5" halves city chance in Rivers).

Building Settings

BUILDING_CHANCE (default 0.3) controls what percentage of city chunks contain buildings versus streets. Floor counts are configured with four values: BUILDING_MINFLOORS (0), BUILDING_MINFLOORS_CHANCE (4), BUILDING_MAXFLOORS_CHANCE (6), and BUILDING_MAXFLOORS (9). The min and max chance values define the typical range, while the absolute min and max set the hard limits. Basement levels follow a similar pattern with BUILDING_MINCELLARS (0) and BUILDING_MAXCELLARS (4).

Custom Assets

The mod loads building parts, palettes, and city styles from JSON asset files. The default assets include standard palettes, desert palettes, Chisel mod palettes, highway parts, rail parts, monorail parts, and building parts. You can add custom assets by placing a userassets.json file in the lostcities config directory (paths starting with '$' are loaded from the config folder). This allows you to define custom building designs, new block palettes, or entirely new city styles.

Server Configuration

For servers running version 1.12.2, set the level-type to "lostcities" in server.properties (or "lostcities_bop" for Biomes O' Plenty compatibility). For 1.14.4 and later, the world must be configured in singleplayer first, then uploaded to the server. The world type setting in the server needs to match the uploaded world's configuration. The ADAPTING_WORLDTYPES setting allows the mod to work with other world type mods that support the IChunkPrimerFactory API.

Mod Compatibility

The Lost Cities is designed to work with several other mods. Biomes O' Plenty integration is built-in, with a dedicated config flag (DIMENSION_BOP) that enables BoP biomes in the Lost Cities dimension. The Chisel mod has its own dedicated profile that uses Chisel blocks for building construction via special palette files (palette_chisel.json and palette_chisel_desert.json). Since the mod uses vanilla Spawners, any modded mobs that use the vanilla spawn system will appear in the dark interiors of city buildings, making the mod naturally more dangerous in modpacks with additional hostile mobs.

The Realistic profile includes custom generator options with terrain noise parameters similar to Quark's realistic worldgen. This creates more natural-looking terrain around and between cities with parameters like a coordinate scale of 175, height scale of 75, biome depth weight of 1.2, and a biome scale weight of 3.4. The mod also supports adapting to other world types through the ADAPTING_WORLDTYPES config, as long as those world types implement the IChunkPrimerFactory API.