University of Birmingham's Old Joe has 7,000 Twitter followers
Old Joe is the world’s tallest freestanding clock tower, standing at the heart of the University of Birmingham since 1905.
The 100-metre tower is named after the university’s first chancellor Joseph Chamberlain, a famous political son of Birmingham, who raised funds for its construction.
It has its own Twitter account, with 7,000 followers.
Old Joe's glowing clock face is believed to have been the inspiration for the Eye of Sauron in JRR Tolkien's The Lord of the Rings trilogy.
He also has an asteroid named in his honour - Asteroid 10515 Old Joe.
The four clock faces also change colour on special dates in the calendar.
And once a week, someone has to climb Old Joe to check his clock is keeping the correct time for students.
Video journalist: John Bray