I was inspired to write an article after looking at this amazing photo. According to the website EXPLORINGGB.COM, "The Great Barn at Harmondsworth is the largest standing medieval timber-framed structure in Britain."  It was built in 1425 and still stands proudly today. Bear in mind that there were no nails in this construction; the timbers were held together with mortise and tenon joinery. You will often see pegs driven through the joint to lock it in place. This carpentry joinery has been implemented for the last 7000 years, so it's no surprise we are still using it today, It was very important for barns, which needed a large space in the middle of the floor for threshing grain—in …