Philippine National Railway
Manila-Biñan
You think the MRT or LRT is the densest place on Earth but they would not come close to the non electric train by the Philippine National Railway. Used to be feared by many as the most unwanted transportation system in the country because of the decayed cabins and the tracks that used to be inches away from houses which are vulnerable to be run over by the train if not careful has now evolved into its real purpose as a functioning train system minus the side tenants.