diff --git a/.changeset/nine-kangaroos-marry.md b/.changeset/nine-kangaroos-marry.md
new file mode 100644
index 0000000000..dbb5e3ba98
--- /dev/null
+++ b/.changeset/nine-kangaroos-marry.md
@@ -0,0 +1,5 @@
+---
+"hardhat": patch
+---
+
+Fixed an issue when forking networks like Arbitrum Nitro that use non-standard transaction types (#2995, #3194).
diff --git a/packages/hardhat-core/src/internal/hardhat-network/provider/fork/ForkBlockchain.ts b/packages/hardhat-core/src/internal/hardhat-network/provider/fork/ForkBlockchain.ts
index d70b63d7de..745d11befe 100644
--- a/packages/hardhat-core/src/internal/hardhat-network/provider/fork/ForkBlockchain.ts
+++ b/packages/hardhat-core/src/internal/hardhat-network/provider/fork/ForkBlockchain.ts
@@ -24,6 +24,7 @@ import { ReadOnlyValidTransaction } from "../transactions/ReadOnlyValidTransacti
 import { HardhatBlockchainInterface } from "../types/HardhatBlockchainInterface";
 
 import { ReadOnlyValidEIP1559Transaction } from "../transactions/ReadOnlyValidEIP1559Transaction";
+import { ReadOnlyValidUnknownTypeTransaction } from "../transactions/ReadOnlyValidUnknownTypeTransaction";
 import { rpcToBlockData } from "./rpcToBlockData";
 import { rpcToTxData } from "./rpcToTxData";
 
@@ -297,9 +298,20 @@ export class ForkBlockchain
           rpcToTxData(transaction) as FeeMarketEIP1559TxData
         );
       } else {
-        throw new InternalError(
-          `Unknown transaction type ${transaction.type.toString()}`
-        );
+        // we try to interpret unknown txs as legacy transactions, to support
+        // networks like Arbitrum that have non-standards tx types
+        try {
+          tx = new ReadOnlyValidUnknownTypeTransaction(
+            new Address(transaction.from),
+            Number(transaction.type),
+            rpcToTxData(transaction)
+          );
+        } catch (e: any) {
+          throw new InternalError(
+            `Could not process transaction with type ${transaction.type.toString()}`,
+            e
+          );
+        }
       }
 
       block.transactions.push(tx);
diff --git a/packages/hardhat-core/src/internal/hardhat-network/provider/transactions/ReadOnlyValidUnknownTypeTransaction.ts b/packages/hardhat-core/src/internal/hardhat-network/provider/transactions/ReadOnlyValidUnknownTypeTransaction.ts
new file mode 100644
index 0000000000..38c75c556e
--- /dev/null
+++ b/packages/hardhat-core/src/internal/hardhat-network/provider/transactions/ReadOnlyValidUnknownTypeTransaction.ts
@@ -0,0 +1,162 @@
+import { Common } from "@nomicfoundation/ethereumjs-common";
+import { Transaction, TxData, TxOptions } from "@nomicfoundation/ethereumjs-tx";
+import { Address } from "@nomicfoundation/ethereumjs-util";
+
+import { InternalError } from "../../../core/providers/errors";
+
+/* eslint-disable @nomiclabs/hardhat-internal-rules/only-hardhat-error */
+
+/**
+ * This class is like `ReadOnlyValidTransaction` but for
+ * a transaction with an unknown tx type.
+ */
+export class ReadOnlyValidUnknownTypeTransaction extends Transaction {
+  public static fromTxData(_txData: TxData, _opts?: TxOptions): never {
+    throw new InternalError(
+      "`fromTxData` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+    );
+  }
+
+  public static fromSerializedTx(
+    _serialized: Buffer,
+    _opts?: TxOptions
+  ): never {
+    throw new InternalError(
+      "`fromSerializedTx` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+    );
+  }
+
+  public static fromRlpSerializedTx(
+    _serialized: Buffer,
+    _opts?: TxOptions
+  ): never {
+    throw new InternalError(
+      "`fromRlpSerializedTx` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+    );
+  }
+
+  public static fromValuesArray(_values: Buffer[], _opts?: TxOptions): never {
+    throw new InternalError(
+      "`fromRlpSerializedTx` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+    );
+  }
+
+  public readonly common: Common;
+
+  private readonly _sender: Address;
+  private readonly _actualType: number;
+
+  constructor(sender: Address, type: number, data: TxData = {}) {
+    super(data, { freeze: false });
+
+    this.common = this._getCommon();
+    this._sender = sender;
+    this._actualType = type;
+  }
+
+  public get type(): number {
+    return this._actualType;
+  }
+
+  public verifySignature(): boolean {
+    return true;
+  }
+
+  public getSenderAddress(): Address {
+    return this._sender;
+  }
+
+  public sign(): never {
+    throw new InternalError(
+      "`sign` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+    );
+  }
+
+  public getDataFee(): never {
+    throw new InternalError(
+      "`getDataFee` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+    );
+  }
+
+  public getBaseFee(): never {
+    throw new InternalError(
+      "`getBaseFee` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+    );
+  }
+
+  public getUpfrontCost(): never {
+    throw new InternalError(
+      "`getUpfrontCost` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+    );
+  }
+
+  public validate(_stringError?: false): never;
+  public validate(_stringError: true): never;
+  public validate(_stringError: boolean = false): never {
+    throw new InternalError(
+      "`validate` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+    );
+  }
+
+  public toCreationAddress(): never {
+    throw new InternalError(
+      "`toCreationAddress` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+    );
+  }
+
+  public getSenderPublicKey(): never {
+    throw new InternalError(
+      "`getSenderPublicKey` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+    );
+  }
+
+  public getMessageToVerifySignature(): never {
+    throw new InternalError(
+      "`getMessageToVerifySignature` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+    );
+  }
+
+  public getMessageToSign(): never {
+    throw new InternalError(
+      "`getMessageToSign` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+    );
+  }
+}
+
+// Override private methods
+
+const ReadOnlyValidUnknownTypeTransactionPrototype: any =
+  ReadOnlyValidUnknownTypeTransaction.prototype;
+
+ReadOnlyValidUnknownTypeTransactionPrototype._validateTxV = function (
+  _v: any,
+  common: any
+) {
+  return this._getCommon(common);
+};
+
+ReadOnlyValidUnknownTypeTransactionPrototype._signedTxImplementsEIP155 =
+  function () {
+    throw new InternalError(
+      "`_signedTxImplementsEIP155` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+    );
+  };
+
+ReadOnlyValidUnknownTypeTransactionPrototype._unsignedTxImplementsEIP155 =
+  function () {
+    throw new InternalError(
+      "`_unsignedTxImplementsEIP155` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+    );
+  };
+
+ReadOnlyValidUnknownTypeTransactionPrototype._getMessageToSign = function () {
+  throw new InternalError(
+    "`_getMessageToSign` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+  );
+};
+
+ReadOnlyValidUnknownTypeTransactionPrototype._processSignature = function () {
+  throw new InternalError(
+    "`_processSignature` is not implemented in ReadOnlyValidUnknownTypeTransaction"
+  );
+};