# Tutorial: Bridging Assets

> The bridge contract address is essential for facilitating communication and asset transfers between Layer 1 (L1) and Layer 2 (L2) networks

> For the complete documentation index, see [llms.txt](/docs/llms.txt).

# OP Stack

To bridge funds using **OP Stack**, follow these steps:

1. **Select Sepolia Network in MetaMask**

   * Ensure that your MetaMask wallet is connected to the **Sepolia Test Network**

2. **Send Tokens to the Bridge Address**

   * Obtain the **bridge contract address** for your OP Stack devnet from the **Alchemy Rollup page**

     * Log in to your Alchemy account
     * Go to the Rollups page from the Chain section
     * Access or create your OP Stack rollup
     * Copy the Bridge Address

   * Send **ETH** or **ERC-20 tokens** from Ethereum (Sepolia) to the bridge address

***

# Arbitrum Stack

To bridge funds using **Arbitrum Stack**, follow these steps:

1. **Obtain the Configuration File**

   * Download the configuration file from the **Alchemy Rollup page**

     * Log in to your Alchemy account
     * Go to the Rollups page from the Chain section
     * Access or create your Arbitrum Chain rollup
     * Click on the View Bridge Config button
     * Copy the configuration

2. **Visit the Arbitrum Bridge**

   * Navigate to the official Arbitrum bridge at [https://bridge.arbitrum.io/](https://bridge.arbitrum.io/)

3. **Connect Your Wallet**

   * Open your **MetaMask** wallet and connect it to the bridge

4. **Enable Developer Mode**

   * Go to **Settings** from the top-right corner
   * On the **Developer** section, enable **Testnet Mode**

![](https://alchemyapi-res.cloudinary.com/image/upload/v1764179951/docs/api-reference/alchemy-rollups/c263fbb82bb318747837fc077c426d17c1e6b0eb7dd43759f4fc36ae63675f9a-Screenshot_2025-01-09_at_16.29.03.png)

5. **Import the Configuration File**

* Paste the configuration file details into the bridge interface
* Click **Add Chain** to register your custom rollup network

6. **Bridge Funds**

* In the **bridge interface**, select your custom rollup chain
* Move funds from **Ethereum (L1)** to your **Arbitrum Rollup (L2)**

![](https://alchemyapi-res.cloudinary.com/image/upload/v1764179953/docs/api-reference/alchemy-rollups/de51c446cc59a7c37fa5efa953d6e52d379608caf10d1408e6cebccb9f070d70-Screenshot_2025-01-09_at_16.30.18.png)