The block that started the clock
Block 0 was mined on 3 January 2009, and Satoshi left a message in its coinbase: "The Times 03/Jan/2009 Chancellor on brink of second bailout for banks" — a timestamp and a thesis in one line. Its 50 BTC reward went to the now-legendary address 1A1zP1eP….
By a quirk of bitcoin's original code, that reward was never added to the spendable ledger: the genesis coins are unspendable by protocol. Not lost, not dormant — structurally outside the money supply, forever. (One of the certainties in our lost-coins accounting.)
A monument that accepts donations
People send coins to the genesis address anyway — small tributes accumulating for over a decade and a half, from all over the world, to an address whose owner (if alive) has never touched his fortune. Every satoshi sent here is deliberately burned in bitcoin's first monument. We watch it because the address is confirmed Satoshi's — block 0's coinbase is the one attribution in bitcoin that needs no research — and because if the tributes ever left, that would be a story.