Tauck will resume full operations for all remaining 2021 itineraries this August and September.
The tour operator said it expects it will operate more than 80% of its pre-pandemic inventory this year, with full resumption in 2022.
Earlier this month, Tauck said it would resume some of its operations in stages.
Tauck's most recent announcement this week includes its Danube and Rhine river cruises, land tours in Europe and itineraries in other destinations, from Morocco to Machu Picchu.
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August's restart plans include several itineraries in Italy, as well as land tours in Switzerland, Ireland, Jordan and Egypt. A Rhine river cruise will depart Aug. 25.
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The remainder of 2021's tours and cruises will resume operating in September.
"If a destination is welcoming American travelers, and if it's a place where Tauck operates, we'll be bringing our guests there in the coming months," Tauck CEO Dan Mahar said in a statement.
Mahar did urge caution with the resumption of operations, saying, "We're as prepared as possible, but we know that the best attitude is to expect the unexpected and to stay flexible."