Established in 1913 in Oamaru by Joe Martyn, Martyn's Cycles is still owned and run by his direct descendants and the fourth generation is now working there.
Dave Martyn and his wife, Edna, are the current owner-managers of the business, which started in lower Eden St after Joe Martyn had completed his apprenticeship as a cycle maker and mechanic.
In 1916 it moved to lower Thames St when Mr Martyn bought out Harry Brown's cycle shop, in premises now occupied by Short Black.
It stayed there until 2002, before moving two doors north to its existing premises.
Its present owners are certain it is the oldest cycle shop continuously owned by one family and according to Ride: The story of cycling in New Zealand, by the Kennett Brothers, it is also the oldest cycle shop.
During that time, a ''heap of family'' have been involved in one way or another, Dave Martyn said.
The shop has also changed markedly.
It was the first shop in Oamaru to sell fishing tackle, and the first to have a key and locksmith outlet.
Then toys were added, ending in the stock it carries today.
Mr Martyn said the shop had its hard years through the Depression of the 1930s and during World War 2, when some items were rationed.
For example, an old photograph shows one of the family with a new cycle without tyres.
''They obviously couldn't put tyres on all the new bikes, and I presume you had to wait until they became available,'' he said.
Cycling has also changed.
Before the 1970s there were women's, men's and children's cycles, and little else.
Since then, there have been cycles such as the Raleigh 20s, 10-speed bikes, BMX and mountain bikes and, within those categories, a huge number of varieties.
The latest is cycles with rechargeable batteries, capable of more than 30kmh and distances up to 100km.
And even the old, traditional shapes are making a comeback, some with baskets on the front.
The shop retains the family link, starting with Joe Martyn, then his sons Ron and Ken (Dave's father) and daughter Joyce (Thompson).
Dave's cousin Russell Thompson, the son of Joyce, has had the locksmiths in the shop for more than 20 years.
Ken's daughter Judy also worked there at one time.
The fourth generation, Dave's son Brent, is now working there.
