Rooms at Athens hotels went for 106 euros per night against 111 euros in June, down by 5 percent.
Madrid saw its hotel prices drop this month for a standard double room by 41 percent, down to 90 euros a night.
The room rate was reduced by 18 percent in Paris against June figures, now going for 138 euros per night. Room rates also decreased in Amsterdam by 18 percent compared to June, to 140 euros for a standard double.
Room prices in Vienna and Rome also dropped by 14 percent and 13 percent respectively, to 104 euros and 94 euros per night.
In Istanbul, meanwhile, travelers paid 73 euros per night on average, with the Turkish city recording the highest increase across Europe in July, a 10 percent rise compared to June.
Hotels in Reykjavik also increased room charges by 7 percent against the previous month, to 156 euros.
On a yearly basis, hotel prices for standard rooms in Moscow and Lisbon hotels marked the largest reduction with travelers to the Russian capital paying 58 euros for a standard double room per night, down by 41 percent against the previous year, and in Lisbon 100 euros a night, a 16 percent decrease compared to July 2018.