Ok guys so I’ve kind of built up this idea for an item my players are Persuing for a quest I’ve sent them on and the item is in the center of a mind flayer hive city. I’m trying to find a workable way to design this city that won’t involve them having to fight the hundreds of them that would be there at least not all at once, they just need ways to make it to the center of the city but I’m so out of ideas on how to build an interesting crawl, I can fill it with encounters that shouldn’t be a big deal but more of an issue with how they come to find the entrance to this said sneaky pathway and such. 

Your players will figure it out, you just have to present them with the options.  Going through a closed warehouse, abandoned/off hour factory, alley-ways, sewage tunnels, or even convincing disguise gear and more.  There are endless ways to get through a city virtually undetected.  As it stands, unless the city itself is on high-alert for trespassers, it shouldn't be too difficult to navigate through unless the players end up calling attention to themselves.