Sandstone was long quarried at two sites in what is now the city centre. If you walk along Royal Terrace Gardens you may notice the mounds which run alongside the street. These mounds are part of two sites which were known as the Upper and Lower Quarry Holes or the London Road Quarries.
No longer immediately obvious, these quarries had an interesting history. In 1650, guns were positioned in the holes to try to thwart Cromwell's advance on Edinburgh. They were also a favourite position for duels right up until the mid 18th century as well as being a place considered ideal for private discussion; no doubt a place where walls DIDN'T have ears! In 1557 the Earls of Arran and Huntly met there to discuss in secret Mary of Guise's activities.
Sadly, quite a few people came to an untimely end by falling into the quarries. The owners of the quarries were ordered to fill them in in 1677 but they were left open until the mid-1700s. In 1717 a murderer, Robert Irvine, was hanged nearby and his body was commanded to be "interred in the Quarry-hole near to the Tup Well" (watch out for his ghost!). The quarries were still being used to source stone in 1761 by a certain William Jameson, who was granted permission by the Town Council to extract stone for work he was doing at the back of the Canongate.
The quarries were ultimately closed in 1766 when the City Treasurer was given the authority to "pay the Town's proportion of filling up the quarry at Nether Quarryholes".
It is hard to believe nowadays, as you walk through this busy urban area, that these quarries even existed - but if you look hard enough the traces are there!
Info: "Building Stones of Edinburgh", Bunyan, Fairhurst, Mackie and McMilllan, EGS, 1987.