Police say the man, who's not yet been named, died at around 6.40pm on 18 September.
Police say the 66-year-old died in a single vehicle accident on the track to Fort Clonque, at Alderney's south-western tip.
They say as investigations are carried out there will be a police presence in the area and ask people to stay away.
Scorecard for people in Guernsey to monitor their alcohol intake
Every household will get a scratchcard which will reveal whether their alcohol consumption is at the recommended safe level.
Plans to sell Guernsey rectory
St Martin's parish constables say repairs to the rectory building would be a financial burden on ratepayers.
Thousands of new species discovered in Guernsey’s freshwater habitats
Scientists say the results of Guernsey's first island-wide environmental DNA survey are "nothing short of incredible."
Guernsey Post to end air deliveries
Little uptake means the Special Delivery by air trial will end in early October.
Channel Islands Pride: What's on where?
The Channel Islands Pride Parade is in Guernsey for 2026, and there's lots to do whether you're walking in the Parade or cheering from the sidelines.
18 months before work can begin on resurfacing Alderney's runway
The delay is because a new design is needed now that the runway does not need to be widened.
Guernsey man reflects on surviving 9/11 on the 25th anniversary
Today, 11 September 2026, marks a quarter of a century since the deadliest terrorist attacks in human history.
Temporary traffic lights removed from key St Peter Port route sooner than expected
Temporary traffic lights expected to be in the Charroterie for 19 months have been removed - after just a couple of weeks.
