But workmen digging up a city centre car park yesterday afternoon could never have expected to make such a lively discovery.
Four Second World War hand grenades and hundreds of used bullets were unearthed during excavation work in Melville Street, just a few days after 100 live bullets were found on the same site.
A bomb disposal team raced to the scene as buildings on the street were evacuated.
It is thought the weapons may have been left there by a member of the Home Guard after the war.
Site agent John Carlin, who works for Sundial Properties, which was carrying out refurbishment work, said: “We thought that was it after Monday’s find, but as soon as one of the guys dug down again he unearthed a load of fired shells and a piece of hessian sack.
“When he tugged on the hessian, a grenade popped out and we all stepped away pretty quick.”
The workmen had been digging in the rear car park of the property and had only burrowed three or four feet when they made the alarming find.
Mr Carlin said experts had told him the ammunition had most likely been stashed on the site by a former soldier.
He said: “I’ve worked on hundreds of old buildings and never come across something like this.
“The bomb disposal crew think that they must belong to a former Home Guard troop as seemingly after the war a lot of this additional ammunition was just kept. Most of it ended up buried in back gardens. It’s fascinating but frightening at the same time.”
Last night, more than 300 sandbags were drafted into the property as a detailed excavation of the site was carried out ahead of a planned controlled explosion this morning.
A police spokesman said: “We received a call at 3.45pm that a grenade was uncovered during the excavation of a garden. A cordon was put in place and we will release further details in due course.”
In May 2010, a similar grenade was discovered by a janitor cleaning out a cupboard in an Edinburgh University building on Buccleuch Place.
Hours earlier, another scare in Spottiswoode Gardens, Livingston, saw a bomb disposal team called out, only for a suspect device to be declared an imitation.
In May 2007, the Cancer Research shop in Morningside Road had to be evacuated after a Second World War grenade was discovered among donations. Bomb disposal experts later made the device safe.