"This must be the wood," she said thoughtfully to herself, "where things have no names. I wonder what'll become of MY name when I go in? I shouldn't like to lose it at all . . . .“ She was rambling on in this way when she reached the wood: it looked very cool and shady. "Well, at any rate it's a great comfort," she said as she stepped under the trees, "after being so hot, to get into the – into WHAT?" . . . . She stood silent for a minute, thinking: then she suddenly began again. "Then it really HAS happened, after all! And now, who am I?" —Through the Looking Glass, Lewis Carroll

Which detail is stated explicitly in the passage?
Alice has reached the wood.
Alice is afraid of the wood.
Alice cannot find the wood.
Alice has lost her name.

According to the excerpt from Through the Looking Glass by Lewis Carroll, it is narrated that Alice is close to the woods were names don't exist and she is scared of losing/forgetting her name. However, some moments later she can't remember who she is as she has lost her name.

Therefore, the explicit detail given is that Alice has reached the woods as earlier stated by the author which makes her lose her name.