Forum adverts like this one are shown to any user who is not logged in. Join us by filling out a tiny 3 field form and you will get your own, free, dakka user account which gives a good range of benefits to you: No adverts like this in the forums anymore. Times and dates in your local timezone. Full tracking of what you have read so you can skip to your first unread post, easily see what has changed since you last logged in, and easily see what is new at a glance. Email notifications for threads you want to watch closely. Being a part of the oldest wargaming community on the net. If you are already a member then feel free to login now.

Here are some images first so you can get a clear idea of what i mean.
http://www.forgeworld.co.uk/Warhammer-40000/Imperial_Guard/Death-Korps-of-Krieg/DEATH_KORPS_OF_KRIEG-MARS-ALPHA-PATTERN-LEMAN-RUSS-ANNIHILATOR-COMPLETE-KIT.html

The back of the Valdor.
http://www.forgeworld.co.uk/Warhammer-40000/Imperial_Guard/Imperial_Guard_Super_Heavy_Tanks/VALDOR-TANK-HUNTER.html

http://www.forgeworld.co.uk/Warhammer-40000/Imperial_Guard/Death-Korps-of-Krieg/DEATH_KORPS_OF_KRIEG_MARS_ALPHA_PATTERN_LEMAN_RUSS_VANQUISHER_COMPLETE_KIT.html

What are these 'Trench Rails' I am aware of the name but have no idea of any practical application for them. I assume they are some through back to WW1 seeing as the krieg are a pastiche but i just can't guess how they would be used.

Help me Dakka! Aid me with your near fetishistic obsession with militeria.

They're for crossing trenches.

Tanks could easily get stuck in a trench, IIRC, one of the most famous pictures of a Mk1 is one stuck in a German anti-tank hole/trench.

I'm not sure how they work but I think they worked by providing both a counter balance and a leaver for getting out of a trench.

Trench rails are there to prevent it from falling backwards and getting stuck when crossing a narrow trench.