Minecraft wiki entry for Secret_door, associated text: When entering a minecart, the player instantly teleports. Additionally, minecarts can be entered through lava. These mechanics can be exploited to get through a stream of lava. To build it, first, build an entrance and cover it with lava. Try to make it look like a natural lavafall. Behind the lava, place a rail and put a minecart on it. If in survival, be careful not to get burned by the lava.