Translation of installation in Spanish

I am Spanish Teacher. I graduated last year, in August. I studied mostly in Germany. I have been working for nine months as a teacher in many language schools but soon I will be a student again.
We joined the mass and climbed it. The stones were a little slippery and I doubt that this place is accident free. Climbing big slippery stones was not an easy task but we managed it slowly.
The town on the other side of the border is called Arica. You immediately see the difference to Peru. Fast food chains, brand names and modern stores appear all over the city.