See voy:fr:Modèle:Routes for how it works

The code works as follows:

Quick code to copy

{{routebox2
| temp1=
| directionl1=
| majorl1=
| minorl1=
| directionr1=
| majorr1=
| minorr1=
| temp1a=
| temp1b=
| temp1c=
}}

Here's an explanation of how this template works

{{routebox2
| temp1= Insert the first template into this parameter here. Use the full template so to enter line M2 for Copenhagen, enter {{rint|copenhagen|M2}}
| directionl1=Which direction should the left point out to
| majorl1=Major destination that should show up on the left
| minorl1=Minor destination that should show up on the left
| directionr1=Which direction should the right point out to
| majorr1=Major destination that should show up on the left
| minorr1=Minor destination that should show up on the left
| temp1a=Any second route number on the same line (if a network has two lines such as E8 and Highway 21 in Finland)
| temp1b=Any third route number on the same line (if a network has three lines)
| temp1c=Any fourth route number on the same line (if a network has four lines)
}}

A long full copy of this template can be found here which can be used to cut and paste. A quick way to insert this template is to enter {{subst:rb2}}