These Mastiff Calendars feature this large, massive, symmetrical dog with a well-knit frame. They are one of the heaviest breeds in the world, weighing up to 200 pounds! They give the impression of grandeur and dignity. They have been developed into a guardian, and few intruders would venture onto a property guarded by a Mastiff, yet they are a much loved family dog with a gentle side. Mastiffs have been used since Roman times as guard dogs and dogs of war. They are very aware of what is going on around them, and will act accordingly to anything unusual. Mastiffs tend to keep close to home and are disinclined to roam. Unknown to most people, the Mastiff is a gentle giant. They are surprisingly gentle, caring and calm. They remain easygoing, loyal and protective. Mastiffs are excellent guards, and have been used as such for nearly their entire known history. They can be possessive of their home, their owner, and even their owner's car. They are excellent with children if they are socialized when they are young, and they are perfect for the loving person who wants a kindly gentle dog with defensive capabilities. Mastiff Calendars.