A supermarket's plans to expand a car park could ruin the last chance to investigate part of the Battle of Tewkesbury's site, it has been claimed.
The Tewkesbury Battlefield Society believe a small plot of grass near to the town's Aldi is the scene of the battle's "fiercest fighting".
One objector said finds from the site could bring "kudos" similar to the discovery of Richard III in a car park.
The battle of Tewkesbury was fought during the Wars of the Roses in 1471.
The proposal was unanimously voted through at a council meeting on Thursday.
But members of the society believe an archaeological dig should take place before the car park is expanded.
Several objections were sent to Tewkesbury Borough Council, with one calling the archaeologist's report "fundamentally flawed".
'Worth the delay'
The objection said: "there are very few undisturbed areas of the battlefield remaining, so this represents a rare opportunity to investigate a part that has lain untouched... possibly since the battle itself.
"The application must include an archaeological investigation before the site is either buried under tarmac, or, worse, destroyed."
Another said: "not that we think any kings are under there, but one only has to look at recent developments in Leicester to show what kudos could be brought to the town if any finds were made.
"Surely the time and effort is worth the short delay?"
The official archaeologist's report said the site was the subject of an archaeological dig in 2011 and "no significant remains were observed", recommending that no investigation needs to take place.