Cross-Chain Bridge: How Crypto Moves Between Blockchains

When you send Ethereum from one network to Solana, you’re using a cross-chain bridge, a system that connects separate blockchains so tokens and data can move between them. Also known as blockchain interoperability protocol, it’s what lets you trade assets without being locked into one chain. Without these bridges, your Bitcoin would stay on Bitcoin, your ETH on Ethereum, and your SOL on Solana—no mixing, no swapping, no flexibility.

These bridges are the invisible pipelines behind DeFi, gaming, and multi-chain wallets. They rely on smart contracts, validators, or oracles to lock tokens on one side and mint equivalent ones on the other. But they’re not magic. Many have been hacked—over $2 billion lost since 2020—because of weak security or centralization. A DeFi bridge, a type of cross-chain bridge designed for decentralized finance applications might let you use your USDC on Avalanche, but if the bridge’s code has a flaw, your funds vanish. That’s why users check audits, token supply locks, and whether the bridge is backed by a reputable team.

Some bridges are built for speed, like those connecting Polygon to Ethereum. Others focus on privacy, like those used in zk-rollups. And some are just temporary fixes—built for a single token, with no long-term plan. You’ll see this in the posts below: projects like sidechain, a parallel blockchain that connects to a mainnet to improve scalability are often confused with bridges, but they’re different. Sidechains are siblings to the main chain; bridges are connectors between strangers.

The real question isn’t just how bridges work—it’s which ones you can trust. Some let you move tokens in seconds. Others take hours. Some charge pennies. Others drain your wallet. And some? They disappear overnight. The posts here cut through the noise: you’ll find real breakdowns of bridge risks, examples of failed bridges, and what to look for before you click ‘Bridge Tokens.’ No fluff. Just what happens when crypto tries to cross borders.