States say visitor numbers are up 7% on the 2024.
Castle Cornet, Fort Grey and the German Signals HQ close this weekend for the '25 season.
The exception is the Castle, which will be open on Remembrance Sunday between 10am and 1pm.
A drop in cruise ship visits dented visitor numbers to the Castle but the States say increased French day trippers compensated for this.
On the 80th anniversary of the Liberation, visitors to the German radio command bunker at St Jacques rose 20%.
Looking back on the season, Guernsey Museums' Helen Glencross says it's been positive:
"We’re delighted to see such strong engagement from both local people and visitors.
"The popularity of events like Castle Nights and Twilight Cinema shows how much these historic sites mean to the community.
"In addition, the rise in French tourism is a really positive trend, and we’re looking forward to building on that success."
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