An alley or pathway which is dark, long and scary. It will usually be coined Rape Alley by the locals due to the fact that it looks like the sort of place someone would get raped. Many towns and areas have a "rape alley" and it will often be used in conversation when giving directions to a house party or purchasing illegal substances.
Person 1: Where shall I meet you?
Person 2: Meet me by Rape Alley, I'll be there in 10 minutes