That part isn't too long. It leads to the meat of Day 5 which is pretty awesome.

Also there's the Warehouse. It's completely optional and not super long but can be pretty tough and might require some grinding before hand. Just know that at some point in Day 5 there's a point of no return and you won't be able to go back there or any previous areas.

@pr1mus I just started on Day 5. I'm located in the Sewers in Chinatown. I'm hoping this doesn't take long.

Day 5 is by far the longest. Almost half the total length of the game. So it really depends on where you are in Day 5.

Edit: Well maybe not half but at least a third of it.

@pr1mus I thought the game was longer. I'm already on Day 5 right now, so I'm sure that I'm missing a lot of things. I feel that I'm going way too fast with this one.

Parasite Eve is the greatest game of 1998. Don't ever let anyone tell you otherwise. If you take the time to fully explore everywhere a first playthrough can take around 10-12 hours from my experience. It's not super long.