This is the first block in the Bitcoin blockchain. The genesis block was hardcoded in the bitcoin core software. It is in the chainparams.cpp file (https://github.com/bitcoin/bitcoin/blob/master/src/chainparams.cpp):
static CBlock CreateGenesisBlock(uint32_t nTime, uint32_t nNonce, uint32_t nBits, int32_t nVersion, const CAmount& genesisReward)
{
const char* pszTimestamp = "The Times 03/Jan/2009 Chancellor on brink of second bailout for banks";
const CScript genesisOutputScript = CScript() << ParseHex("04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5f") << OP_CHECKSIG; return CreateGenesisBlock(pszTimestamp, genesisOutputScript, nTime, nNonce, ...
