The findings come from the most recent edition of the European Tourism Trends and Prospects quarterly report from the ETC, which monitors the Covid-19 impact on the sector.
However, it did find that all reporting European destinations still enjoyed higher levels of hotel occupancy this summer compared to 2020, based on data for July-September.
Several destinations reported occupancy rates close to 70%, including the UK, Slovenia, Monaco and Turkey.
European air passenger growth also gained momentum over the months of June (-69%), July (-57%) and August (-49%) compared to 2019, although global revenue passenger kilometres (RPKs) in August remained half of pre-Covid-19 levels.
Although the report claimed that European travel has made "positive strides" in 2021, it said there is still a "long road ahead" as international tourist arrivals to Europe were down 77% half-way through the year.
The ETC observed a notable absence of long-haul travellers, with US arrivals to Europe remaining 90% below their 2019 levels for one third of reporting destinations.
The absence of Chinese holidaymakers was also felt across the continent, with all reporting destinations posting declines over 90% compared to 2019.
Overall, international tourist arrivals to Europe are forecast to be 60% below 2019 by the end of 2021 with many other factors continuing to weigh on Europe’s tourism recovery.
Luis Araujo, ETC’s president, said it is clear to see the "critical role" vaccination programmes have played in helping travel rebound.
"The Covid-19 vaccine rollout was vital to the easing of entry requirements and boosting the appeal of travel during the summer season," he continued.
"However, vaccination efforts won’t be enough. As the winter months approach, it is imperative that Europe strives to further restore the freedom of movement by implementing more holistic and coherent approaches for travel within and outside the EU."
