Pasto is more of a city that you stopover for the night on your way to the border of Ecuador and Colombia, South America. I spent the night at the Hotel Koala Inn. Seems you ought to be aware of your surroundings once it starts getting dark. The city of Pasto seems to be suffering from a graffiti problem, because once you walk around you will notice it on many buildings.
There are some beautiful churches to look at.
You will find plenty of restaurants and pastry shops to keep your hunger at bay in the center part of town.
I caught a cab to the center of town, but there are plenty of hotels around the bus terminal if you want to save money.