diff --git a/README.md b/README.md
index 287ea52..a994790 100644
--- a/README.md
+++ b/README.md
@@ -53,7 +53,7 @@ use Symfony\Component\Cache\Adapter\RedisAdapter;
 use Symfony\Contracts\Cache\CacheInterface;
 
 $orchHttpClient = new OrchHttpClient("https://orch.vanilla.localhost", "access-token-here");
-$siteProvider = new OrchSiteProvider($orchHttpClient, OrchCluster::REGION_AMS1_PROD1);
+$siteProvider = new OrchSiteProvider($orchHttpClient, [OrchCluster::REGION_AMS1_PROD1]);
 
 // It is highly recommended to set a user-agent for network requests.
 $siteProvider->setUserAgent("my-service:1.0");
@@ -71,7 +71,7 @@ $cache = new MemcachedAdapter(/** Configuration here. */);
 $siteProvider->setCache($cache);
 
 # Region can be changed later
-$siteProvider->setRegionID(OrchCluster::REGION_YUL1_PROD1);
+$siteProvider->setRegionIDs([OrchCluster::REGION_YUL1_PROD1, OrchCluster::REGION_AMS1_PROD1]);
 ```
 
 The orchestration provider needs to be configured with an authenticated `OrchHttpClient` and a region/network to load sites from.
@@ -117,8 +117,7 @@ function doSomethingWithCluster(Cluster $cluster)
 {
     // A few getters
     $clusterID = $cluster->getClusterID();
-    $region = $cluster->getRegion();
-    $network = $cluster->getNetwork();
+    $regionID = $cluster->getRegionID();
 }
 
 function doSomethingWithSite(Site $site)
diff --git a/src/Cluster.php b/src/Cluster.php
index 778b405..aec4256 100644
--- a/src/Cluster.php
+++ b/src/Cluster.php
@@ -16,12 +16,15 @@ class Cluster
     public const REGION_AMS1_PROD1 = "ams1-prod1";
     public const REGION_SJC1_PROD1 = "sjc1-prod1";
     public const REGION_LOCALHOST = "localhost";
+    public const REGION_MOCK = "mock";
+
     public const VALID_REGIONS = [
         self::REGION_YUL1_DEV1,
         self::REGION_YUL1_PROD1,
         self::REGION_AMS1_PROD1,
         self::REGION_SJC1_PROD1,
         self::REGION_LOCALHOST,
+        self::REGION_MOCK,
     ];
 
     private string $clusterID;
diff --git a/src/Local/LocalSite.php b/src/Local/LocalSite.php
index f69b90e..cfd0329 100644
--- a/src/Local/LocalSite.php
+++ b/src/Local/LocalSite.php
@@ -27,18 +27,13 @@ class LocalSite extends Site
      * @param string $configPath
      * @param SiteRecord $siteRecord
      * @param LocalSiteProvider $siteProvider
-     * @param HttpHandlerInterface $httpHandler
      *
      * @psalm-suppress InvalidArgument
      */
-    public function __construct(
-        string $configPath,
-        SiteRecord $siteRecord,
-        LocalSiteProvider $siteProvider,
-        HttpHandlerInterface $httpHandler
-    ) {
+    public function __construct(string $configPath, SiteRecord $siteRecord, LocalSiteProvider $siteProvider)
+    {
         $this->configPath = $configPath;
-        parent::__construct($siteRecord, $siteProvider, $httpHandler);
+        parent::__construct($siteRecord, $siteProvider);
     }
 
     /**
diff --git a/src/Local/LocalSiteProvider.php b/src/Local/LocalSiteProvider.php
index 3d65856..12bb3ab 100644
--- a/src/Local/LocalSiteProvider.php
+++ b/src/Local/LocalSiteProvider.php
@@ -7,6 +7,7 @@
 namespace Garden\Sites\Local;
 
 use Garden\Http\CurlHandler;
+use Garden\Sites\Cluster;
 use Garden\Sites\Exceptions\ConfigLoadingException;
 use Garden\Sites\SiteProvider;
 use Garden\Sites\SiteRecord;
@@ -31,7 +32,7 @@ class LocalSiteProvider extends SiteProvider
      */
     public function __construct(string $siteConfigFsBasePath)
     {
-        parent::__construct("localhost");
+        parent::__construct([Cluster::REGION_LOCALHOST]);
         $this->siteConfigFsBasePath = $siteConfigFsBasePath;
     }
 
@@ -95,7 +96,7 @@ public function getSite(int $siteID): LocalSite
 
         $configPath = $siteRecord->getExtra("configPath") ?? "";
 
-        $localSite = new LocalSite($this->siteConfigFsBasePath . $configPath, $siteRecord, $this, new CurlHandler());
+        $localSite = new LocalSite($this->siteConfigFsBasePath . $configPath, $siteRecord, $this);
         return $localSite;
     }
 
diff --git a/src/Mock/MockCluster.php b/src/Mock/MockCluster.php
new file mode 100644
index 0000000..bdfa3ab
--- /dev/null
+++ b/src/Mock/MockCluster.php
@@ -0,0 +1,23 @@
+<?php
+/**
+ * @copyright 2009-2023 Vanilla Forums Inc.
+ * @license Proprietary
+ */
+
+namespace Garden\Sites\Mock;
+
+use Garden\Sites\Cluster;
+
+/**
+ * Cluster for usage in mocks.
+ */
+class MockCluster extends Cluster
+{
+    /**
+     * @param string $clusterID
+     */
+    public function __construct(string $clusterID)
+    {
+        parent::__construct($clusterID, Cluster::REGION_MOCK);
+    }
+}
diff --git a/src/Mock/MockSite.php b/src/Mock/MockSite.php
new file mode 100644
index 0000000..2aa0b34
--- /dev/null
+++ b/src/Mock/MockSite.php
@@ -0,0 +1,181 @@
+<?php
+/**
+ * @copyright 2009-2023 Vanilla Forums Inc.
+ * @license Proprietary
+ */
+
+namespace Garden\Sites\Mock;
+
+use Garden\Sites\Local\LocalCluster;
+use Garden\Sites\Site;
+use Garden\Sites\SiteRecord;
+use Garden\Utils\ArrayUtils;
+
+/**
+ * A mock local site for testing purposes.
+ *
+ * @extends Site<MockSite, LocalCluster>
+ */
+class MockSite extends Site
+{
+    public const MOCK_CLUSTER_ID = "cl00000";
+
+    /** @var int */
+    public int $maxJobConcurrency = 25;
+
+    /** @var string */
+    protected string $baseUrl;
+
+    /** @var array<array-key, mixed>|\ArrayAccess  */
+    protected $config;
+
+    /**
+     * Constructor.
+     *
+     * @param string $baseUrl
+     * @param int $siteID
+     * @param array $config
+     * @param string $clusterID
+     * @param MockSiteProvider|null $mockSiteProvider
+     */
+    public function __construct(
+        string $baseUrl,
+        int $siteID = MockSiteProvider::MOCK_SITE_ID,
+        array $config = [],
+        string $clusterID = self::MOCK_CLUSTER_ID,
+        MockSiteProvider $mockSiteProvider = null
+    ) {
+        $this->baseUrl = $baseUrl;
+        $this->config = $config;
+        $siteRecord = new SiteRecord($siteID, 0, $clusterID, $baseUrl);
+        parent::__construct($siteRecord, new MockSiteProvider());
+        $this->generateKey();
+        $this->setSystemToken("test123");
+        $this->setConfigs([
+            "Vanilla.AccountID" => 1,
+            "queue.disableFeedback" => true,
+        ]);
+    }
+
+    /**
+     * @param MockSiteProvider $mockSiteProvider
+     * @return void
+     */
+    public function setSiteProvider(MockSiteProvider $mockSiteProvider): void
+    {
+        $this->siteProvider = $mockSiteProvider;
+    }
+
+    /**
+     * @return SiteRecord
+     */
+    public function getSiteRecord(): SiteRecord
+    {
+        return $this->siteRecord;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    protected function loadSiteConfig(): array
+    {
+        return $this->config;
+    }
+
+    /**
+     * Set config values for the site.
+     *
+     * @param array<string, mixed> $configs
+     *
+     * @return void
+     */
+    public function setConfigs(array $configs): void
+    {
+        foreach ($configs as $key => $val) {
+            ArrayUtils::setByPath($key, $this->config, $val);
+        }
+        $this->clearConfigCache();
+    }
+
+    /**
+     * Generate a random private key.
+     */
+    public function generateKey(): void
+    {
+        $privateKey = bin2hex(random_bytes(32));
+        $this->setPrivateKey($privateKey);
+    }
+
+    /**
+     * Set the config private key.
+     *
+     * @param string|null $key
+     */
+    public function setPrivateKey(?string $key): void
+    {
+        $this->config["VanillaQueue"]["Keys"]["Private"] = $key;
+    }
+
+    /**
+     * Set a value for the Garden.Scheduler.Token config field.
+     *
+     * @param string|null $value
+     * @return void
+     */
+    public function setSchedulerToken(?string $value): void
+    {
+        $this->config["Garden"]["Scheduler"]["Token"] = $value;
+    }
+
+    /**
+     * Set Api Key
+     *
+     * @param string|null $key
+     * @return void
+     */
+    public function setSystemToken(?string $key): void
+    {
+        ArrayUtils::setByPath(self::CONF_SYSTEM_ACCESS_TOKEN, $this->config, $key);
+    }
+
+    /**
+     * Set Site Account id
+     *
+     * @param int $accountID
+     * @return void
+     */
+    public function setAccountID(int $accountID): void
+    {
+        $this->config["Vanilla"]["AccountID"] = $accountID;
+    }
+
+    /**
+     * Set Elastic Secret
+     *
+     * @param ?string $secret
+     * @return void
+     */
+    public function setElasticSecret(?string $secret): void
+    {
+        $this->config["ElasticDev"]["Secret"] = $secret;
+    }
+
+    /**
+     * Set the site Plugins.
+     *
+     * @param array $plugins
+     * @return void
+     */
+    public function setPlugins(array $plugins): void
+    {
+        $this->config["Plugins"] = $plugins;
+    }
+
+    /**
+     * @return string
+     */
+    public function getSearchServiceBaseUrl(): string
+    {
+        return "https://fake-search-service.test";
+    }
+}
diff --git a/src/Mock/MockSiteProvider.php b/src/Mock/MockSiteProvider.php
new file mode 100644
index 0000000..255cc5a
--- /dev/null
+++ b/src/Mock/MockSiteProvider.php
@@ -0,0 +1,86 @@
+<?php
+/**
+ * @copyright 2009-2023 Vanilla Forums Inc.
+ * @license Proprietary
+ */
+
+namespace Garden\Sites\Mock;
+
+use Garden\Sites\Cluster;
+use Garden\Sites\Exceptions\SiteNotFoundException;
+use Garden\Sites\Local\LocalCluster;
+use Garden\Sites\Site;
+use Garden\Sites\SiteProvider;
+use Symfony\Component\Cache\Adapter\NullAdapter;
+
+/**
+ * A Mock LocalSiteProvider for testing purposes.
+ *
+ * @extends SiteProvider<MockSite, LocalCluster>
+ */
+class MockSiteProvider extends SiteProvider
+{
+    const MOCK_SITE_ID = 123;
+
+    /** @var array<int, MockSite> */
+    private array $mockSites = [];
+
+    /**
+     * Constructor.
+     *
+     * @param MockSite ...$mockSites One or more mock sites.
+     */
+    public function __construct(MockSite ...$mockSites)
+    {
+        foreach ($mockSites as $mockLocalSite) {
+            $this->mockSites[$mockLocalSite->getSiteID()] = $mockLocalSite;
+        }
+        parent::__construct([Cluster::REGION_MOCK]);
+        $this->setCache(new NullAdapter());
+    }
+
+    /**
+     * Add a site.
+     *
+     * @param MockSite $mockSite
+     * @return void
+     */
+    public function addSite(MockSite $mockSite): void
+    {
+        $mockSite->setSiteProvider($this);
+        $this->mockSites[$mockSite->getSiteID()] = $mockSite;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    protected function loadAllSiteRecords(): array
+    {
+        $siteRecords = [];
+        foreach ($this->mockSites as $siteID => $site) {
+            $siteRecords[$siteID] = $site->getSiteRecord();
+        }
+
+        return $siteRecords;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function getSite(int $siteID): Site
+    {
+        $site = $this->mockSites[$siteID] ?? null;
+        if ($site === null) {
+            throw new SiteNotFoundException($siteID);
+        }
+        return $site;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    protected function loadAllClusters(): array
+    {
+        return [MockSite::MOCK_CLUSTER_ID => new LocalCluster(MockSite::MOCK_CLUSTER_ID)];
+    }
+}
diff --git a/src/Orch/OrchSite.php b/src/Orch/OrchSite.php
index 4ad5403..2a67f00 100644
--- a/src/Orch/OrchSite.php
+++ b/src/Orch/OrchSite.php
@@ -22,14 +22,10 @@ class OrchSite extends Site
      *
      * @param SiteRecord $siteRecord
      * @param OrchSiteProvider $siteProvider
-     * @param HttpHandlerInterface $httpHandler
      */
-    public function __construct(
-        SiteRecord $siteRecord,
-        OrchSiteProvider $siteProvider,
-        HttpHandlerInterface $httpHandler
-    ) {
-        parent::__construct($siteRecord, $siteProvider, $httpHandler);
+    public function __construct(SiteRecord $siteRecord, OrchSiteProvider $siteProvider)
+    {
+        parent::__construct($siteRecord, $siteProvider);
     }
 
     /**
diff --git a/src/Orch/OrchSiteProvider.php b/src/Orch/OrchSiteProvider.php
index 7dd1e4c..a80ff78 100644
--- a/src/Orch/OrchSiteProvider.php
+++ b/src/Orch/OrchSiteProvider.php
@@ -26,11 +26,11 @@ class OrchSiteProvider extends SiteProvider
      * Constructor.
      *
      * @param OrchHttpClient $orchHttpClient A configured orch client.
-     * @param string $regionID One of the {@link Cluster::REGION_*} constants.
+     * @param string[] $regionIDs One or more of the {@link Cluster::REGION_*} constants.
      */
-    public function __construct(OrchHttpClient $orchHttpClient, string $regionID)
+    public function __construct(OrchHttpClient $orchHttpClient, array $regionIDs)
     {
-        parent::__construct($regionID);
+        parent::__construct($regionIDs);
         $this->orchHttpClient = $orchHttpClient;
     }
 
@@ -71,7 +71,7 @@ protected function loadAllSiteRecords(): array
     public function getSite(int $siteID): OrchSite
     {
         $siteRecord = $this->getSiteRecord($siteID);
-        $site = new OrchSite($siteRecord, $this, new CurlHandler());
+        $site = new OrchSite($siteRecord, $this);
         return $site;
     }
 
diff --git a/src/Site.php b/src/Site.php
index e629e4c..f9f36b7 100644
--- a/src/Site.php
+++ b/src/Site.php
@@ -6,6 +6,7 @@
 
 namespace Garden\Sites;
 
+use Garden\Http\CurlHandler;
 use Garden\Http\HttpHandlerInterface;
 use Garden\Sites\Clients\SiteHttpClient;
 use Garden\Sites\Exceptions\BadApiCredentialsException;
@@ -36,13 +37,12 @@ abstract class Site implements \JsonSerializable
     /**
      * @param SiteRecord $siteRecord
      * @param SiteProvider<TSite, TCluster> $siteProvider
-     * @param HttpHandlerInterface $httpHandler
      */
-    public function __construct(SiteRecord $siteRecord, SiteProvider $siteProvider, HttpHandlerInterface $httpHandler)
+    public function __construct(SiteRecord $siteRecord, SiteProvider $siteProvider)
     {
         $this->siteRecord = $siteRecord;
         $this->siteProvider = $siteProvider;
-        $this->httpHandler = $httpHandler;
+        $this->httpHandler = new CurlHandler();
     }
 
     /**
diff --git a/src/SiteProvider.php b/src/SiteProvider.php
index cdd808f..7cb765c 100644
--- a/src/SiteProvider.php
+++ b/src/SiteProvider.php
@@ -23,30 +23,30 @@ abstract class SiteProvider
 
     protected string $userAgent = "vanilla-sites-package";
 
-    /** @var string The region sites should be loaded from. */
-    protected string $regionID;
+    /** @var string[] The region sites should be loaded from. */
+    protected array $regionIDs;
 
     /**
      * Constructor.
      *
-     * @param string $regionID One of the {@link Cluster::REGION_*} constants
+     * @param string[] $regionIDs One or more of the {@link Cluster::REGION_*} constants
      */
-    public function __construct(string $regionID)
+    public function __construct(array $regionIDs)
     {
         $this->cache = new ArrayAdapter();
-        $this->regionID = $regionID;
+        $this->regionIDs = $regionIDs;
     }
 
     /**
      * Set the region we should be filtering too.
      *
-     * @param string $regionID
+     * @param string[] $regionIDs
      *
      * @return void
      */
-    public function setRegionID(string $regionID): void
+    public function setRegionIDs(array $regionIDs): void
     {
-        $this->regionID = $regionID;
+        $this->regionIDs = $regionIDs;
     }
 
     /**
@@ -201,7 +201,7 @@ public function getClusters(): array
         });
 
         $filteredClusters = array_filter($allClusters, function (Cluster $cluster) {
-            return $cluster->getRegionID() === $this->regionID;
+            return in_array($cluster->getRegionID(), $this->regionIDs);
         });
 
         return $filteredClusters;
diff --git a/tests/BaseSitesTestCase.php b/tests/BaseSitesTestCase.php
index d011b18..1454cfa 100644
--- a/tests/BaseSitesTestCase.php
+++ b/tests/BaseSitesTestCase.php
@@ -45,7 +45,7 @@ abstract public function provideExpectedSites(): iterable;
     public function testSiteClientBaseUrl(ExpectedSite $expectedSite)
     {
         $provider = $this->siteProvider();
-        $provider->setRegionID($expectedSite->expectedRegionID);
+        $provider->setRegionIDs([$expectedSite->expectedRegionID]);
         $site = $provider->getSite($expectedSite->getSiteID());
         $siteClient = $site->httpClient();
         $siteClient->setThrowExceptions(false);
@@ -66,7 +66,7 @@ public function testSiteClientBaseUrl(ExpectedSite $expectedSite)
     public function testSiteClientAuth(ExpectedSite $expectedSite): void
     {
         $provider = $this->siteProvider();
-        $provider->setRegionID($expectedSite->expectedRegionID);
+        $provider->setRegionIDs([$expectedSite->expectedRegionID]);
         $site = $provider->getSite($expectedSite->getSiteID());
         $siteClient = $site->httpClient();
         $siteClient->setThrowExceptions(false);
@@ -100,7 +100,7 @@ public function testSiteClientAuth(ExpectedSite $expectedSite): void
     public function testValidSites(ExpectedSite $expectedSite): void
     {
         $provider = $this->siteProvider();
-        $provider->setRegionID($expectedSite->expectedRegionID);
+        $provider->setRegionIDs([$expectedSite->expectedRegionID]);
         $site = $provider->getSite($expectedSite->getSiteID());
         $expectedSite->assertMatchesSite($site);
         $expectedSite->assertConfigsMatchSite($site);
diff --git a/tests/MockSitesTest.php b/tests/MockSitesTest.php
new file mode 100644
index 0000000..1224a82
--- /dev/null
+++ b/tests/MockSitesTest.php
@@ -0,0 +1,31 @@
+<?php
+/**
+ * @copyright 2009-2023 Vanilla Forums Inc.
+ * @license Proprietary
+ */
+
+namespace Garden\Sites\Tests;
+
+use Garden\Sites\Mock\MockSite;
+use Garden\Sites\Mock\MockSiteProvider;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * Tests for the mock sites.
+ */
+class MockSitesTest extends TestCase
+{
+    /**
+     * @return void
+     */
+    public function testSharedInstances()
+    {
+        $site1 = new MockSite("https://some-url.com", 1);
+        $site2 = new MockSite("https://some-url.com", 2);
+        $siteProvider = new MockSiteProvider($site1);
+        $siteProvider->addSite($site2);
+
+        $this->assertSame($site1, $siteProvider->getSite(1));
+        $this->assertSame($site2, $siteProvider->getSite(2));
+    }
+}
diff --git a/tests/OrchSitesTest.php b/tests/OrchSitesTest.php
index e70dc10..dd48d8e 100644
--- a/tests/OrchSitesTest.php
+++ b/tests/OrchSitesTest.php
@@ -48,7 +48,7 @@ public function siteProvider(): OrchSiteProvider
             $this->fail("Mock handler wasn't configured");
         }
         $orchClient->setHandler($this->mockHandler);
-        $orchProvider = new OrchSiteProvider($orchClient, Cluster::REGION_YUL1_DEV1);
+        $orchProvider = new OrchSiteProvider($orchClient, [Cluster::REGION_YUL1_DEV1]);
 
         $requestRoot = __DIR__ . "/mock-orch";
         $requestPaths = iterator_to_array(FileUtils::iterateFiles($requestRoot, "/.*\.json$/"));
@@ -161,7 +161,7 @@ public function provideSiteFiltering(): iterable
     public function testSiteFiltering(string $regionID, array $expectedSiteIDs)
     {
         $siteProvider = $this->siteProvider();
-        $siteProvider->setRegionID($regionID);
+        $siteProvider->setRegionIDs([$regionID]);
         $allSites = $siteProvider->getSites();
 
         $this->assertCount(count($expectedSiteIDs), $allSites);