diff --git a/composer.json b/composer.json
index b65f8a8..9f2895f 100644
--- a/composer.json
+++ b/composer.json
@@ -7,6 +7,7 @@
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         "doctrine/doctrine-bundle": "^1.8",
         "doctrine/orm": "^2.6",
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diff --git a/composer.lock b/composer.lock
index 4d5c7f4..186d91d 100644
--- a/composer.lock
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@@ -1092,6 +1092,54 @@
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+                    "homepage": "https://paragonie.com"
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+                "csprng",
+                "pseudorandom",
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@@ -1282,18 +1330,154 @@
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@@ -1349,20 +1533,20 @@
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+                "url": "https://api.github.com/repos/symfony/http-kernel/zipball/194bd224ec27952eac6d4fea6264b22990834eca",
+                "reference": "194bd224ec27952eac6d4fea6264b22990834eca",
                 "shasum": ""
             },
             "require": {
@@ -2078,7 +2262,7 @@
                 "psr/log": "~1.0",
                 "symfony/debug": "~3.4|~4.0",
                 "symfony/event-dispatcher": "~3.4|~4.0",
-                "symfony/http-foundation": "~3.4|~4.0"
+                "symfony/http-foundation": "~3.4.4|~4.0.4"
             },
             "conflict": {
                 "symfony/config": "<3.4",
@@ -2143,7 +2327,7 @@
             ],
             "description": "Symfony HttpKernel Component",
             "homepage": "https://symfony.com",
-            "time": "2018-01-05T08:54:25+00:00"
+            "time": "2018-01-29T13:27:08+00:00"
         },
         {
             "name": "symfony/lts",
@@ -2324,16 +2508,16 @@
         },
         {
             "name": "symfony/polyfill-mbstring",
-            "version": "v1.6.0",
+            "version": "v1.7.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/polyfill-mbstring.git",
-                "reference": "2ec8b39c38cb16674bbf3fea2b6ce5bf117e1296"
+                "reference": "78be803ce01e55d3491c1397cf1c64beb9c1b63b"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/polyfill-mbstring/zipball/2ec8b39c38cb16674bbf3fea2b6ce5bf117e1296",
-                "reference": "2ec8b39c38cb16674bbf3fea2b6ce5bf117e1296",
+                "url": "https://api.github.com/repos/symfony/polyfill-mbstring/zipball/78be803ce01e55d3491c1397cf1c64beb9c1b63b",
+                "reference": "78be803ce01e55d3491c1397cf1c64beb9c1b63b",
                 "shasum": ""
             },
             "require": {
@@ -2345,7 +2529,7 @@
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "1.6-dev"
+                    "dev-master": "1.7-dev"
                 }
             },
             "autoload": {
@@ -2379,20 +2563,20 @@
                 "portable",
                 "shim"
             ],
-            "time": "2017-10-11T12:05:26+00:00"
+            "time": "2018-01-30T19:27:44+00:00"
         },
         {
             "name": "symfony/routing",
-            "version": "v4.0.3",
+            "version": "v4.0.4",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/routing.git",
-                "reference": "a34b58ed26cc090f99b2ef833d609a6884581b3c"
+                "reference": "a69bd948700b672e036147762f46749bcae33796"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/routing/zipball/a34b58ed26cc090f99b2ef833d609a6884581b3c",
-                "reference": "a34b58ed26cc090f99b2ef833d609a6884581b3c",
+                "url": "https://api.github.com/repos/symfony/routing/zipball/a69bd948700b672e036147762f46749bcae33796",
+                "reference": "a69bd948700b672e036147762f46749bcae33796",
                 "shasum": ""
             },
             "require": {
@@ -2457,20 +2641,20 @@
                 "uri",
                 "url"
             ],
-            "time": "2018-01-04T15:52:56+00:00"
+            "time": "2018-01-16T18:04:12+00:00"
         },
         {
             "name": "symfony/yaml",
-            "version": "v4.0.3",
+            "version": "v4.0.4",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/yaml.git",
-                "reference": "b84f646b9490d2101e2c25ddeec77ceefbda2eee"
+                "reference": "ffc60bda1d4a00ec0b32eeabf39dc017bf480028"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/yaml/zipball/b84f646b9490d2101e2c25ddeec77ceefbda2eee",
-                "reference": "b84f646b9490d2101e2c25ddeec77ceefbda2eee",
+                "url": "https://api.github.com/repos/symfony/yaml/zipball/ffc60bda1d4a00ec0b32eeabf39dc017bf480028",
+                "reference": "ffc60bda1d4a00ec0b32eeabf39dc017bf480028",
                 "shasum": ""
             },
             "require": {
@@ -2515,7 +2699,7 @@
             ],
             "description": "Symfony Yaml Component",
             "homepage": "https://symfony.com",
-            "time": "2018-01-03T07:38:00+00:00"
+            "time": "2018-01-21T19:06:11+00:00"
         },
         {
             "name": "zendframework/zend-code",
@@ -2628,7 +2812,7 @@
     "packages-dev": [
         {
             "name": "symfony/dotenv",
-            "version": "v4.0.3",
+            "version": "v4.0.4",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/dotenv.git",
diff --git a/config/packages/doctrine.yaml b/config/packages/doctrine.yaml
index ac8aba0..26d2579 100644
--- a/config/packages/doctrine.yaml
+++ b/config/packages/doctrine.yaml
@@ -10,6 +10,8 @@ doctrine:
 
         # With Symfony 3.3, remove the `resolve:` prefix
         url: '%env(resolve:DATABASE_URL)%'
+        types:
+                uuid: Ramsey\Uuid\Doctrine\UuidType
     orm:
         auto_generate_proxy_classes: '%kernel.debug%'
         naming_strategy: doctrine.orm.naming_strategy.underscore
diff --git a/src/Entity/Event.php b/src/Entity/Event.php
new file mode 100644
index 0000000..1fd7769
--- /dev/null
+++ b/src/Entity/Event.php
@@ -0,0 +1,67 @@
+<?php declare(strict_types = 1);
+
+namespace App\Entity;
+use Doctrine\ORM\Mapping as ORM;
+use Ramsey\Uuid\Uuid;
+use Ramsey\Uuid\UuidInterface;
+
+/**
+ * @ORM\Entity
+ */
+class Event
+{
+	/**
+	 * @var UuidInterface
+	 *
+	 * @ORM\Id
+	 * @ORM\Column(type="Uuid", unique=true)
+	 */
+	protected $id;
+
+
+	/**
+	 * @var string
+	 *
+	 * @ORM\Column(type="string", length=256)
+	 */
+	protected $title;
+
+	/**
+	 * @var string
+	 *
+	 * @ORM\Column(type="text")
+	 */
+	protected $description;
+
+	/**
+	 * @var EventType
+	 * @ORM\ManyToOne(targetEntity="EventType")
+	 */
+	protected $eventType;
+
+	public function __construct(string $title, EventType $eventType) {
+		$this->id = Uuid::uuid4();
+		$this->title = $title;
+		$this->eventType = $eventType;
+	}
+
+	public function getId(): UuidInterface {
+		return $this->id;
+	}
+
+	public function getTitle(): string {
+		return $this->title;
+	}
+
+	public function setTitle(string $title): void {
+		$this->title = $title;
+	}
+
+	public function getEventType(): EventType {
+		return $this->eventType;
+	}
+
+	public function setEventType(EventType $eventType): void {
+		$this->eventType = $eventType;
+	}
+}
diff --git a/src/Entity/EventType.php b/src/Entity/EventType.php
new file mode 100644
index 0000000..ceba819
--- /dev/null
+++ b/src/Entity/EventType.php
@@ -0,0 +1,56 @@
+<?php declare(strict_types = 1);
+
+namespace App\Entity;
+use Doctrine\ORM\Mapping as ORM;
+
+/**
+ * @ORM\Entity
+ */
+class EventType
+{
+	/**
+	 * @var int
+	 *
+	 * @ORM\Id
+	 * @ORM\Column(type="integer")
+	 * @ORM\GeneratedValue
+	 */
+	protected $id;
+
+	/**
+	 * @var string
+	 * @ORM\Column(type="string", length=64, unique=true)
+	 */
+	protected $name;
+
+	/**
+	 * @var string|null
+	 * @ORM\Column(type="string", nullable=true, length=512)
+	 */
+	protected $comment;
+
+	public function __construct(string $name, ?string $comment = null) {
+		$this->name = $name;
+		$this->comment = $comment;
+	}
+
+	public function getId(): int {
+		return $this->id;
+	}
+
+	public function getName(): string {
+		return $this->name;
+	}
+
+	public function setName(string $name): void {
+		$this->name = $name;
+	}
+
+	public function getComment(): ?string {
+		return $this->comment;
+	}
+
+	public function setComment(?string $comment): void {
+		$this->comment = $comment;
+	}
+}
diff --git a/src/Entity/SubEvent.php b/src/Entity/SubEvent.php
new file mode 100644
index 0000000..37a587b
--- /dev/null
+++ b/src/Entity/SubEvent.php
@@ -0,0 +1,112 @@
+<?php declare(strict_types = 1);
+
+namespace App\Entity;
+use Doctrine\ORM\Mapping as ORM;
+use Ramsey\Uuid\Uuid;
+use Ramsey\Uuid\UuidInterface;
+
+/**
+ * @ORM\Entity
+ */
+class SubEvent
+{
+	/**
+	 * @var UuidInterface
+	 *
+	 * @ORM\Id
+	 * @ORM\Column(type="Uuid", unique=true)
+	 */
+	protected $id;
+
+	/**
+	 * @var Event
+	 *
+	 * @ORM\ManyToOne(targetEntity="Event")
+	 */
+	protected $parent;
+
+	/**
+	 * @var string
+	 *
+	 * @ORM\Column(type="string", length=256)
+	 */
+	protected $title;
+
+	/**
+	 * @var string
+	 *
+	 * @ORM\Column(type="text")
+	 */
+	protected $description;
+
+	/**
+	 * @var \DateTime
+	 *
+	 * @ORM\Column(type="datetimetz")
+	 */
+	protected $startDate;
+
+	public function __construct() {
+		$this->id = Uuid::uuid4();
+	}
+
+	/**
+	 * @var \DateTime
+	 *
+	 * @ORM\Column(type="datetimetz")
+	 */
+	protected $endDate;
+
+	public function __construct(Event $parent, string $title, string $description, \DateTime $startDate, \DateTime $endDate) {
+		$this->id = Uuid::uuid4();
+		$this->parent = $parent;
+		$this->title = $title;
+		$this->description = $description;
+		$this->startDate = $startDate;
+		$this->endDate = $endDate;
+	}
+
+	public function getId(): UuidInterface {
+		return $this->id;
+	}
+
+	public function getParent(): Event {
+		return $this->parent;
+	}
+
+	public function setParent(Event $parent): void {
+		$this->parent = $parent;
+	}
+
+	public function getTitle(): string {
+		return $this->title;
+	}
+
+	public function setTitle(string $title): void {
+		$this->title = $title;
+	}
+
+	public function getDescription(): string {
+		return $this->description;
+	}
+
+	public function setDescription(string $description): void {
+		$this->description = $description;
+	}
+
+	public function getStartDate(): \DateTime {
+		return $this->startDate;
+	}
+
+	public function setStartDate(\DateTime $startDate): void {
+		$this->startDate = $startDate;
+	}
+
+	public function getEndDate(): \DateTime {
+		return $this->endDate;
+	}
+
+	public function setEndDate(\DateTime $endDate): void {
+		$this->endDate = $endDate;
+	}
+}
diff --git a/symfony.lock b/symfony.lock
index 5dc50b3..6c4e946 100644
--- a/symfony.lock
+++ b/symfony.lock
@@ -65,6 +65,9 @@
     "ocramius/proxy-manager": {
         "version": "2.1.1"
     },
+    "paragonie/random_compat": {
+        "version": "v2.0.11"
+    },
     "psr/cache": {
         "version": "1.0.1"
     },
@@ -77,6 +80,18 @@
     "psr/simple-cache": {
         "version": "1.0.0"
     },
+    "ramsey/uuid": {
+        "version": "3.7.3"
+    },
+    "ramsey/uuid-doctrine": {
+        "version": "1.3",
+        "recipe": {
+            "repo": "github.com/symfony/recipes-contrib",
+            "branch": "master",
+            "version": "1.3",
+            "ref": "f7895777cd673fcefbc321a9063077a24e5df646"
+        }
+    },
     "symfony/cache": {
         "version": "v4.0.3"
     },