Denver

Denver is a city overrun with feral dogs.

Background
The city was annexed by Caesar's Legion after they assimilated the Hangdogs, a tribe who inhabited the outskirts of the city. The packs of dogs in the city are mentioned to be dangerous, swarming their targets and tearing them apart.

A tribe of people had previously learned how to live with the dogs, treating the feral hounds as spirit animals, companions in the post-nuclear world. When Caesar's Legion arrived, the Hangdogs were assimilated and their culture wiped out, apart from their skill with dogs, with many being made houndmasters.

Legate Lanius lost many men to a combination of factors in Denver, including supply lines stretched to the breaking point, and dogs that killed many. The city remains dominated by feral dog packs which may include pre-War police cyberdogs,  and the Legion still procures its best dogs from the city.

Appearances
Denver is mentioned in Fallout: New Vegas and its add-on Lonesome Road.