A recent study by Overnight Glasses identified the summer vacation destinations where eye protection is most needed.
The research analyzed 46 global travel spots using four metrics: UV Index, average summer sunshine hours, temperature, and humidity. Each variable was normalized from 0–100 and combined into an Eye Protection Index. Locations at higher altitudes were flagged due to elevated UV intensity. Data sources included global climate databases and UV records for summer 2024.
| Destination | UV index during peak season | Average Hours of sunshine in summer. | Composite Score |
| Cairo | 12 | 11.0 | 98.02 |
| Dubai | 11 | 10.8 | 87.43 |
| Athens | 10 | 11.7 | 84.76 |
| Marrakech | 10 | 10.0 | 78.81 |
| Madrid | 9 | 11.3 | 75.03 |
| Tirana | 9 | 10.7 | 74.25 |
| Bali | 11 | 10.0 | 72.89 |
| Sydney | 13 | 6.3 | 70.19 |
| Cozumel | 12 | 7.5 | 69.88 |
| Kuala Lumpur | 12 | 6.0 | 68.82 |
To access the full research, please follow the link.
Cairo ranks first as the summer destination where maximum protection is needed, with a composite score of 98. The city has a UV index of 12 and 11 hours of sunshine per day—both among the highest observed. It combines prolonged exposure with high-intensity radiation, making it the most demanding environment for eye protection this summer.
Dubai comes in second with a score of 87.4, trailing Cairo by over 10 points. Its UV index of 11 and 10.8 sunshine hours create similarly challenging conditions, though slightly moderated by lower average humidity. While the difference is modest, travelers may find Dubai’s dry desert climate slightly less taxing on the eyes than Cairo’s extended daylight.
Athens ranks third with a score of 84.7, and it leads the top five in daylight exposure at 11.7 hours. Compared to Dubai, Athens offers lower UV intensity (index of 10) but more prolonged sunlight, indicating a shift from radiation-driven to duration-driven eye risk. Unlike the dry environments ranked higher, Athens’ Mediterranean humidity can also affect eye comfort differently.
In fourth, Marrakech earns a score of 78.8, falling just below Athens. With a UV index of 10 and 10 sunshine hours, it mirrors Athens in UV exposure but lags in daylight length. Compared to Athens’ humid warmth, Marrakech’s dry and arid conditions introduce a different type of discomfort—heightening eye dryness and sensitivity in desert air.
Madrid is fifth and scores 75, just below Marrakech. It matches Athens in sunshine duration (11.3 hours) but carries a slightly lower UV index of 9. While its Mediterranean conditions are more temperate than the North African cities ranked above, Madrid’s long days still present sustained exposure that adds up quickly, especially in summer’s peak.
Tirana closely follows Madrid with a score of 74.2. With 10.7 sunshine hours and a UV index of 9, it falls short of the intensity seen in higher-ranked cities. Compared to Madrid, Tirana has less daylight and a more humid summer, which can offer minor relief from dryness—but not enough to reduce the need for protective eyewear.
Bali takes seventh position, with a score of 72.9. While it enjoys 10 hours of sunlight and registers a high UV index of 11, its tropical humidity offers a stark contrast to Tirana’s continental climate. Unlike the previous cities where sunlight duration plays a major role, Bali’s threat stems more from the intensity of UV—even on cloudy or humid days.
Sydney comes in eighth, with a score of 70.2. Despite having just 6.3 sunshine hours, it records the highest UV index of 13. As the only Southern Hemisphere city on this list, it presents unexpected UV intensity during its winter months.
Cozumel ranks ninth with a score of 69.9, featuring a UV index of 12 and 7.5 hours of sunlight. While its sun duration is longer than Sydney’s, its UV intensity is slightly lower. Compared to Bali, Cozumel offers similar tropical exposure, but the potential for reflection from coastal waters makes sun exposure more multi-directional.
Kuala Lumpur rounds out the top 10 with a score of 68.8. Its UV index of 12 equals Cozumel’s, but its sunshine duration is just 6 hours, the lowest in this ranking. While it has less exposure time, its dense humidity and cloud-filtered UV create deceptively intense conditions, requiring sunglasses even on overcast days—something less pronounced in Cozumel.
A spokesperson from Overnight Glasses commented on the study: “UV exposure isn’t just about how long the sun is out—it’s about how strong that radiation is and how your environment interacts with it. Desert cities, tropical coasts, and even high-altitude urban areas can present equally harsh risks, but in very different ways. For travelers, the key takeaway is that eye protection isn’t just for long beach days—it’s necessary in any destination where UV radiation is consistently strong.”