An inspiring pensioner has finished his incredible fourth round of climbing all 282 of Scotland's Munros.

Colin Lees, 71, was in his mid-50s when the mountains first came calling, and after his initial foray with a local rambling club, he says he "never looked back".

After a lifetime of running in marathons, playing football six times a week and playing squash, the retired electrical engineer from Fife was in prime shape to take on Scotland's peaks.

A Munro is any mountain in Scotland over 3000ft high and is named after Sir Hugh Munro who first produced the list in 1891.

Colin scaled all 282 peaks for the first time by 2004. He then completed his second round in 2007, his third in 2011, and he has now successfully bagged his fourth.

He completed the 3,074 foot high Beinn Na Lap near Corrour in the Central Highlands last month with his two grandchildren Ailsa, 11, and Innes, 8, along with his daughter Kim, 44.

Colin, who now volunteers at his local British Heart Foundation shop, says: "I do question my sanity sometimes.

"When I first started walking Munros, I never thought I'd complete one full set - never mind four.

"Before I'd ever climbed a hill I thought I was reasonably fit but after I finished it I was sore for weeks."

Unlike Colin, Sir Hugh Munro himself never did complete all the ascents; at the time of his death he had omitted Carn an Fhidhleir and Carn Cloich-mhuillin (which was demoted in 1981 and which he was saving until last as it was nearest to his home).

He never climbed the Inaccessible Pinnacle ("In Pinn") on Skye but this was not regarded as a Munro on his original list.

Instead, the Reverend A. E. Robertson became the first to complete the summits, in 1901. The final mountain reached was Meall Dearg (on the Aonach Eagach) - where the reverend famously kissed first the cairn, and then his wife.

The real explosion in the popularity of Munro-bagging came in the late 1980s and today the numbers are huge.

Like most sports, Munro bagging has a language of its own. Each summit reached is another bagged, and a step closer to the coveted 'compleation' of a round, which is when a walker has climbed all 282 Munros like Colin has.

Those who climb all the summits are, following tradition, known as 'compleaters' or as a 'Munroist'.

Though it's not quite clear if there is a unique name for a compleater like Colin who manages to bag them all more than once.

"My daughter Kim was initially quite worried about me getting lost while walking so she got me a GPS which I've brought with me ever since my first round," he says.

"The physically hardest ones are probably the five at Fisherfield in the north-west of the country.

"I try to do them all slightly differently but one time I started in the dark hours of the morning then 13 hours later I was finished. That's probably the most difficult."

Despite his success, Colin says he isn't quite sure if he'll make a go of bagging them all for a fifth time though.

"I've worn out a lot of boots over the years but this will probably be the last time I climb all of them," he says.

"Your enjoyment of each attempt really hinges on the unpredictable Scottish weather but it's almost always worth it."