Travel through time

How did I get here? Blue sky above. I can feel the sin on my skin.
 The train races and the stone walls zoom by. Moss and trees.
It smells of earth and summer. Where am I?

The tracks run forward, but I don't know where.
I can't remember. There's something missing.

A bridge.
A short tunnel and something else behind.

Something stirs inside me. 

Darkness ahead. Sweat runs down my spine.
I don't want to go.
We shouldn't go.
we mustn't go.

The noise is deafening. My hair lashes across my face.
There's light and there's darkness.
I can see things move at the corner or my eyes.

The lights are fading. my heart beats against my ribcage.
I can hear them come.
I can only make out their shapes in the shadow.

Light at the end of the tunnel,
but I do not dare to hope.
Please let it be true.

I can hear them howl behind me but the train keeps going.
Please, let it be the outside.
Oh please, let me get out of it alive.

I can taste the open air,
The light is blinding.

I brace myself.

  

We are out. I am safe.
The train races ahead, leaving the darkness behind.
I can hear them howl, hungry and furious.

  

 The train races and the stone walls zoom by. Moss and trees.
It smells of earth and summer. Blue sky above. I can feel the sin on my skin.

How did I get here?
Where am I?