1. Popular tourist destinations [cover details like How to Reach? What to see? Where to stay? When to visit?]
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2. Top 10 Lists [Eg. Top 10 Beaches, Top 10 Hotels etc.]
3. Photo/video guides to tourist locations.
4. Technical guides [this would include for example, visa application process, airport rules, customs formalities etc.]
5. General travel tips.
6. Travel deals.
7. Guides to hotels, clubs, restaurants across all popular tourist destinations.
8. Review top travel apps and websites.
9. Embassy details.
10. Country fact-sheet.
11. Local food guide [including street food].
12. Adventure sports destinations.
13. Eco tourism getaways.
14. Holiday planning tips.
15. Hidden Gems: little known places worth visiting.
16. Unusual hotels or restaurants.
17. Do's and don'ts while travelling.
18. Haunted destinations.
19. Popular festivals from across the globe.
20. Religious destinations.
21. People and their culture.
22. Photography tips.
23. Honeymoon destinations and Romantic getaways.
24. Wildlife destinations.
25. The best travel stories and books on travel.
Your travel blog could also feature a forum where fellow wanderers can discuss everything under the sun related to travel.
You can also feature travel articles written by your readers.