diff --git a/MultiversalDiplomacy/Model/Location.cs b/MultiversalDiplomacy/Model/Location.cs
index fe0aae9..ff4d365 100644
--- a/MultiversalDiplomacy/Model/Location.cs
+++ b/MultiversalDiplomacy/Model/Location.cs
@@ -1,3 +1,5 @@
+using System.Text.Json.Serialization;
+
 namespace MultiversalDiplomacy.Model;
 
 /// <summary>
@@ -9,8 +11,12 @@ public class Location
 {
     /// <summary>
     /// The province to which this location belongs.
+    /// </summary>
+    [JsonIgnore]
     public Province Province { get; }
 
+    public string ProvinceName => Province.Name;
+
     /// <summary>
     /// The location's full human-readable name.
     /// </summary>
@@ -29,6 +35,7 @@ public class Location
     /// <summary>
     /// The locations that border this location.
     /// </summary>
+    [JsonIgnore]
     public IEnumerable<Location> Adjacents => this.AdjacentList;
     private List<Location> AdjacentList { get; set; }
 
diff --git a/MultiversalDiplomacy/Model/Map.cs b/MultiversalDiplomacy/Model/Map.cs
index 1ce0c57..ba1ae80 100644
--- a/MultiversalDiplomacy/Model/Map.cs
+++ b/MultiversalDiplomacy/Model/Map.cs
@@ -5,7 +5,13 @@ namespace MultiversalDiplomacy.Model;
 /// <summary>
 /// Encapsulation of the world map and playable powers constituting a Diplomacy variant.
 /// </summary>
-public class Map {
+public class Map
+{
+    /// <summary>
+    /// The map type.
+    /// </summary>
+    public MapType Type { get; }
+
     /// <summary>
     /// The game map.
     /// </summary>
@@ -16,7 +22,7 @@ public class Map {
     /// </summary>
     public ReadOnlyCollection<Power> Powers { get; }
 
-    private Map(IEnumerable<Province> provinces, IEnumerable<Power> powers)
+    private Map(MapType type, IEnumerable<Province> provinces, IEnumerable<Power> powers)
     {
         Provinces = new(provinces.ToList());
         Powers = new(powers.ToList());
@@ -102,7 +108,7 @@ public class Map {
         Power a = new("Alpha");
         Power b = new("Beta");
 
-        return new([lef, cen, rig], [a, b]);
+        return new(MapType.Test, [lef, cen, rig], [a, b]);
     });
 
     public static Map Classical => _Classical.Value;
@@ -553,7 +559,7 @@ public class Map {
             new("Turkey"),
         ];
 
-        return new(provinces, powers);
+        return new(MapType.Classical, provinces, powers);
     });
 
 #endregion Variants
diff --git a/MultiversalDiplomacy/Model/Unit.cs b/MultiversalDiplomacy/Model/Unit.cs
index aebeb3f..736ec33 100644
--- a/MultiversalDiplomacy/Model/Unit.cs
+++ b/MultiversalDiplomacy/Model/Unit.cs
@@ -1,3 +1,5 @@
+using System.Text.Json.Serialization;
+
 namespace MultiversalDiplomacy.Model;
 
 /// <summary>
@@ -18,6 +20,7 @@ public class Unit
     /// <summary>
     /// The province where the unit is.
     /// </summary>
+    [JsonIgnore]
     public Province Province => this.Location.Province;
 
     /// <summary>
@@ -59,11 +62,11 @@ public class Unit
     /// method after accepting a build order.
     /// </summary>
     public static Unit Build(Location location, Season season, Power power, UnitType type)
-        => new Unit(past: null, location, season, power, type);
+        => new(past: null, location, season, power, type);
 
     /// <summary>
     /// Advance this unit's timeline to a new location and season.
     /// </summary>
     public Unit Next(Location location, Season season)
-        => new Unit(past: this, location, season, this.Power, this.Type);
+        => new(past: this, location, season, this.Power, this.Type);
 }
diff --git a/MultiversalDiplomacy/Model/World.cs b/MultiversalDiplomacy/Model/World.cs
index aa3d716..bce3d82 100644
--- a/MultiversalDiplomacy/Model/World.cs
+++ b/MultiversalDiplomacy/Model/World.cs
@@ -1,6 +1,5 @@
 using System.Collections.ObjectModel;
-
-using MultiversalDiplomacy.Orders;
+using System.Text.Json.Serialization;
 
 namespace MultiversalDiplomacy.Model;
 
@@ -12,16 +11,24 @@ public class World
     /// <summary>
     /// The map variant of the game.
     /// </summary>
+    [JsonIgnore]
     public Map Map { get; }
 
+    /// <summary>
+    /// The map variant of the game.
+    /// </summary>
+    public MapType MapType => this.Map.Type;
+
     /// <summary>
     /// The game map.
     /// </summary>
+    [JsonIgnore]
     public ReadOnlyCollection<Province> Provinces => this.Map.Provinces;
 
     /// <summary>
     /// The game powers.
     /// </summary>
+    [JsonIgnore]
     public ReadOnlyCollection<Power> Powers => this.Map.Powers;
 
     /// <summary>
@@ -32,11 +39,13 @@ public class World
     /// <summary>
     /// Lookup for seasons by designation.
     /// </summary>
+    [JsonIgnore]
     public ReadOnlyDictionary<string, Season> SeasonLookup { get; }
 
     /// <summary>
     /// The first season of the game.
     /// </summary>
+    [JsonIgnore]
     public Season RootSeason => GetSeason("a0");
 
     /// <summary>
@@ -219,9 +228,7 @@ public class World
     /// <summary>
     /// A standard Diplomacy game setup.
     /// </summary>
-    public static World Standard => World
-        .WithStandardMap()
-        .AddStandardUnits();
+    public static World Standard => WithStandardMap().AddStandardUnits();
 
     /// <summary>
     /// Get a season by coordinate. Throws if the season is not found.
diff --git a/MultiversalDiplomacyTests/SerializationTest.cs b/MultiversalDiplomacyTests/SerializationTest.cs
index 3d64156..aff12e0 100644
--- a/MultiversalDiplomacyTests/SerializationTest.cs
+++ b/MultiversalDiplomacyTests/SerializationTest.cs
@@ -9,6 +9,21 @@ namespace MultiversalDiplomacyTests;
 
 public class SerializationTest
 {
+    [Test]
+    public void SerializeRoundTrip_NewGame()
+    {
+        JsonSerializerOptions options = new() {
+            WriteIndented = true,
+            PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
+        };
+
+        World world = World.WithStandardMap();
+        string serialized = JsonSerializer.Serialize(world, options);
+        Console.WriteLine(serialized);
+        World? deserialized = JsonSerializer.Deserialize<World>(serialized, options);
+        Assert.That(deserialized, Is.Not.Null, "Failed to deserialize");
+    }
+
     [Test]
     public void SerializeRoundTrip_MDATC_3_A_2()
     {
@@ -32,9 +47,21 @@ public class SerializationTest
         // Serialize the world
         JsonSerializerOptions options = new() {
             WriteIndented = true,
+            PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
         };
         JsonElement serialized = JsonSerializer.SerializeToDocument(setup.World, options).RootElement;
 
+        Assert.That(
+            serialized.EnumerateObject().Select(prop => prop.Name),
+            Is.EquivalentTo(new List<string> {
+                "mapType",
+                "seasons",
+                "units",
+                "retreatingUnits",
+                "orderHistory",
+                "options",
+            }));
+
         // Deserialize the world
         World reserialized = JsonSerializer.Deserialize<World>(serialized)
             ?? throw new AssertionException("Failed to reserialize world");