There are almost 6,000 people aged over 90 holding a driving licence in Wales, figures have revealed.
According to the DVLA, the total number in Britain has topped 100,000 for the first time.
The areas with the highest number of older drivers are Swansea, Cardiff and Carmarthenshire - each with more than 5,000 aged 80 or over, and more than 400 aged 90 or over.
Research suggests the view that older drivers pose a danger is unfounded.
The figures have been obtained through a Freedom of Information request to the DVLA.
It also revealed the number of drivers aged 80 or older in Wales is 72,000.
A Swansea University study in 2016 revealed drivers aged 70 are involved in three to four times fewer accidents than men aged between 17-21.
Professor Charles Musselwhite, from the Centre for Innovative Ageing, who undertook the study, said: "We've looked at those statistics in depth and we don't think that as a cohort older drivers are any more dangerous than other road users."
He told BBC Radio Wales' Good Morning Wales programme older people adapt to worsening health conditions, like failing eye sight and slower reflexes, well.
But he added this could be an issue in future.
"We particularly know very well that older people pick and choose situations they feel comfortable driving in," he said.
"They drive in lower light, they don't drive at night, they might pick times when it's less busy.
"If you're working later on in life you're less able to choose when and where you drive and it could be that people end up driving in situations which they're less comfortable with."
Older drivers are required to fill in a self-assessment every three years declaring they are medically fit to continue driving.
Marina Spear, occupational therapist at Rookwood Hospital's Wales Mobility and Driving Assessment Service, in Cardiff, believes it must be compulsory to have a medical certificate if older drivers want to renew their licence.
"People often don't even know what their medical conditions are. They don't always know they have a diagnosis of dementia or the implications of their medical condition on them.
"If their self awareness into their medical condition is impaired, how can they self declare their conditions?" she said.
The DVLA said police and medical professionals can notify it if there are concerns about a person's health problems.
But it said age alone was not a "reliable indicator" of a person's fitness to drive and that older people continue to drive safely.