L1-L2 and L2-L2 Bridges

Rollups inherit Ethereum security but still live on separate execution environments. Moving ETH, USDC, or app positions between L1 and L2 — or between two L2s — requires bridges with asymmetric timing: deposits are usually quick, withdrawals often are not.

ZK rollups generally finalize batches faster because validity proofs remove the multi-day optimistic challenge period. Third-party liquidity routers can front L1 tokens for a fee if you cannot wait.

L2-to-L2 hops add another layer: you may bridge L1 → Arbitrum → Base through two separate paths, each with its own wrapped token and trust model. Native interoperability standards are improving, but today most users still trace routes manually.