Arrived at Clock Tower in Lawrence this morning and searched all over for the peregrines, only to find the male perched atop the bulb at the tippy top of the weathervane. The Ayer Mill Clock Tower is the world’s largest mill clock. Its four big glass faces are only 6 inches smaller than Big Ben in London. It is the most treasured icon of Lawrence, MA and reaches a height of 267 feet.  This clock tower’s four dials, lit by 125 bulbs on each face, and a 6,000-pound bell make it a well known landmark in the extended Merrimack Valley!