The Beacon Chain goes live

On December 1, 2020, the Beacon Chain went live — a brand-new proof-of-stake chain running *alongside* the existing proof-of-work mainnet, doing no execution yet, just coordinating validators who'd each staked 32 ETH.

A bridge to the future

A one-way deposit, on purpose

To become a validator you sent 32 ETH to a deposit contract on mainnet — a one-way door. That ETH was locked, un-withdrawable, for what turned out to be years (until Shapella in 2023). People staked billions into a chain that did nothing yet, on the promise of what it would become. In hindsight it's one of the more remarkable votes of confidence in crypto's history.

proof-of-work mainnet   ── real transactions (business as usual)
proof-of-stake Beacon   ── validators only, no execution yet
        │                          │
        └───── ~2 years later ─────┘   The Merge fuses them

It was a deliberately careful approach: stand up and battle-test the PoS consensus for nearly two years before trusting it with real transactions. That patience paid off at The Merge in 2022, when the execution layer swapped onto this chain without a hiccup. The Beacon Chain is where Ethereum's proof-of-stake era quietly started.