diff --git a/src/config/chains.json b/src/config/chains.json
index 4afb939..5d2b030 100644
--- a/src/config/chains.json
+++ b/src/config/chains.json
@@ -64,6 +64,19 @@
       "curveRegistry": ""
     }
   },
+  "123420000034": {
+    "chainId": "123420000034",
+    "explorer": "https://blockscout-123420000034.raas-testnet.gelato.digital/",
+    "label": "Event Horizon Testnet",
+    "shortName": "EH-Testnet",
+    "code": "eth",
+    "rpc": "https://rpc-123420000034.raas-testnet.gelato.digital/",
+    "baseCurrencyName": "ETH",
+    "contracts": {
+      "WETH": "0x4200000000000000000000000000000000000006",
+      "curveRegistry": ""
+    }
+  },
   "42161": {
     "chainId": "42161",
     "explorer": "https://arbiscan.io/",
diff --git a/src/config/envs.json b/src/config/envs.json
index 445649e..23fba33 100644
--- a/src/config/envs.json
+++ b/src/config/envs.json
@@ -244,6 +244,24 @@
             "http": "/orion-indexer/"
           }
         }
+      },
+      "123420000034": {
+        "api": "https://trade.orion.xyz/event-horizon",
+        "services": {
+          "aggregator": {
+            "http": "/backend",
+            "ws": "/v1"
+          },
+          "blockchain": {
+            "http": ""
+          },
+          "priceFeed": {
+            "all": "/price-feed"
+          },
+          "indexer": {
+            "http": "/orion-indexer/"
+          }
+        }
       }
     }
   },
diff --git a/src/constants/chains.ts b/src/constants/chains.ts
index 621b947..d875c3f 100644
--- a/src/constants/chains.ts
+++ b/src/constants/chains.ts
@@ -3,6 +3,7 @@ import { SupportedChainId } from '../types.js';
 export const developmentChains = [
   SupportedChainId.BSC_TESTNET,
   SupportedChainId.SEPOLIA,
+  SupportedChainId.EVENT_HORIZON,
 ];
 export const productionChains = [
   SupportedChainId.MAINNET,
diff --git a/src/types.ts b/src/types.ts
index 72ec8dc..54fdbf4 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -95,6 +95,7 @@ export enum SupportedChainId {
 
   BSC_TESTNET = '97',
   SEPOLIA = '11155111',
+  EVENT_HORIZON = '123420000034',
 
   // For testing and debug purpose
   // BROKEN = '0',