The phrase "to reach the summit" means to successfully reach the highest point of a mountain, achieve a goal, or become the best in a particular field or task. Full definition
We can not reach the summit of success without going first through the valley of failure. (relevantmagazine.com)
It is actually possible to attempt a day climb, you will be able to reach the summit in the afternoon if you start early in the morning. (juanderfulpinoy.com)
You will not reach the summit if you have not done the first step... It's in that perspective that I see this development: a very important first step has been taken. (carbonbrief.org)