Trace your steps back. Find chunks of me. Do try to be smart riddle

Trace your steps back. Find chunks of me. Do try to be smart. I go on forever, but the last safe holds my start. Though I’m infinite, there’s only space here for four. Find the chunk that would follow next to open this locked door : Railway Riddles Answer Compartment 301

Solution: Today, I am here with a different question. One of the most asked questions on the internet. Not a meaningful question. There is no clue in the question. We will try to find answers by reasoning entirely. So let’s start.

The correct answer is 2384

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