The red route walking trail at Orford Ness, which is owned by heritage conservation charity National Trust, has been closed until Saturday, September 23 to allow for the caterpillar nests to be cleared.
READ MORE: Warning after caterpillars poisonous to dogs spotted in East Anglia
The Island of Secrets Exhibition and Information Building has also had to close temporarily.
Reuben Denton, from Orford Ness, said the caterpillars had made their nests in brambles that flanked 100 metres of roadway along the route and staff needed to cut back the brambles.
He said: "The caterpillars have been around for years and years, but this year in particular in the UK they are having a bit of a bumper year and there seem to be more of them around."
READ MORE: National Trust makes it easier to visit Orford Ness
The caterpillars are known to cause skin irritation and breathing problems in humans and asthma sufferers in particular are advised to avoid them.
Mr Denton added: "Parts of the site are closed until we can deal with the caterpillars. They are not particularly dangerous, but they can be an irritant."
READ MORE: Suffolk: Behind the scenes at 'top secret' Orford Ness
The reserve was a top secret military site for much of the 20th century and has six 'labs' that were used to test the components of nuclear weapons and form a backdrop to the shingle.
Other military infrastructure includes a World War One radar receiver building and a bomb ballistics building.
The site is considered to be of importance because it is home to an internationally rare and delicate landscape that includes 20% of Europe's vegetated shingle, which is incredibly fragile and can be easily destroyed.
READ MORE: Suffolk news
