The abandoned mine where Elena was going had many entrances and Elena chose to enter the place from an entrance located high up on the body of a tall mountain. When the mine was still active, there was a path here to bring back the ores and stones. But after the mine was abandoned, no one was there to take care of the path and it was badly damaged by various things like the environment and the monsters.
So in the current time, reaching that entrance was hard for any normal people. Only powerful people would be able to reach the spot where the entrance was. So for Elena reaching that entrance was easy. As for the reason why Elena was choosing this particular troublesome path, it was very simple. This entrance was connected to the path that led to the deepest known depth of the mine in the shortest amount of time. That was the reason why Elena was taking this route.
