More architectural education, building fans.
The walkway between the two chimneys is what was known as the Widow's Walk / Watch, and especially prevalent on NE American sailing communities. A popular romantic myth holds that the platform was used to observe vessels at sea. The name is said to come from the wives of mariners, who would watch for their spouses' return, often in vain as the ocean took the lives of the mariners, leaving the women widows.
Alternatively, beyond their use as viewing platforms, they are frequently built around the chimney of the residence, thus creating access to the structure. This allows the residents of the home to pour sand down burning chimneys in the event of a chimney fire in the hope of preventing the house from burning down.
Bonus -
Dalek Relaxation.
