How many double greens does the Old Course at St. Andrews have?

More interesting reading and links of interest

• In the early days the holes were literally the same for the trip out and back. The players would play from different tees but over the same fairways to the same hole in the ground. Eventually, as popularity and numbers increased, the single holes become two holes and separated by a safe distance.
• If you add the numerical values of each two holes that share a green it adds up to 18 – every time. 2 and 16, 3 and 15, 4 and 14, 5 and 13, 6, and 12, 7 and 11, 8 and 10.
• The average size per putting surface is 22,267 square feet compared to 3,500 at Pebble Beach and 6,435 at Augusta.
• The largest double green – 5 and 13 is an enormous 37,846 square feet. Imagine the house you could build on that footprint!
• This article was written in 2010 prior to the British Open being played at St. Andrews. It gives an interesting insight in to the double greens
•  Below is a fun short video with Paul McGinley, 2014 European Ryder Cup captain, that gives us some idea of the size of the green. Especially watch from the one minute mark!