Bitcoin Cash hard fork

For years the Bitcoin community argued about how to scale. One camp wanted bigger blocks so more transactions fit on chain. Another preferred SegWit and second layer systems. On August 1, 2017, at block 478,558, the big block camp split off with a hard fork and created Bitcoin Cash (BCH), starting with 8 MB blocks.

Anyone holding BTC at the fork received the same amount of BCH. Bitcoin itself carried on, activated SegWit a few weeks later, and kept its 1 MB base block size. This is the textbook example of a contentious hard fork: two chains sharing history up to one block and going separate ways after.

Bitcoin's price kept climbing through the rest of 2017, so the split did not slow the rally. Read our hard fork guide for how this differs from a soft fork like SegWit.