The Little Ice Age

 On 24 November 1434, the River Thames in London froze. It was the first recorded instance of the river freezing. In the early 14th century, the Earth cooled down. It went through a 'cool' period called the Little Ice Age. Winters in England became much colder. Between the 17th and 19th centuries, the ice on the River Thames was so thick people sometimes erected tents on it and held fairs there. They were called Frost Fairs. Fortunately, in the mid-19th century, the Earth began to warm again.