The clock at Denver's East High School is adjusted for the time shift

 The clock at Denver's East High School is adjusted for the time shift

A Saturday modification was made to the clock tower, which towers above East High School and the Denver cityscape, in preparation for the impending return to Mountain Standard Time from Daylight Saving Time. At two a.m. on Sunday, clocks will "fall back" by one hour. 

To advance the clock by one hour, crews scaled the clock. The tower rises to a height of 162 feet at its tallest point. 

The National Association of Watch and Clock Collectors' local branch visited East High School to fix the clock and manually reset it. 

"The clock was in a very bad condition and required extensive repair approximately 15 years ago. It had stopped and most likely hadn't operated for ten years. Everything was refurbished and returned to its original state when our club arrived."

In order to have more light later in the day, most Americans move their clocks forward by one hour in the spring. Morning light levels increase when standard time returns.