Space.
Often referred to as 'The Final Frontier' by many adventurous spirits.
At first, humans conquered the biting cold, with the discovery of fire.
Then came agriculture, leading humans into conquering hunger.
And from agriculture, civilisation bloomed.
The growth of humans was exponential, only getting bigger as time flew by.
From barely surviving day by day in the wilderness, to becoming the dominant species of the Earth, they had slowly built up over time.
Humans had gone from nothing but small specks of matter that had nearly faced extinction dozens of times throughout their pitiful existence, to the dominators of the Milky way galaxy.
And this was all before the Primordial Expanse opened up its metaphorical doors to the human race.