You need to get the concept right.
It's tough to build an online community for travellers, even backpackers. There are so many existing communities. You need a more focused concept.
You need to build the first community of its kind.
This is what BackPackingLight has achieved. The founders realized the same discussions repeatedly came up in existing backpacking communiites (lighter gear) and build an entire community around the concept.
- Who is the community for? Frequent backpackers who want the lightest possible backpack.
- What type of community is it? A community of practice (possibly overlaps with the interest category - but mostly practice)
- Why will people participate in this community? They want the best advice and to demonstrate their own expertise.
- What will happen in the community? People will update each other on the best tips about reducing backpack weight.
- What is the goal of the community? To make backpacks as light as possible
This concept also taps into a symbol (backpacking light) of a broader group identity (freedom, travelling often, fitness). People want to associate themselves with this symbol.
In hindsight, it all makes sense. In foresight,you can bet there would be concerns about ignoring the 99% of the travellers market to focus on this group. Most organizations refuse to do this. Yet this is what must be done. You get to slice of a sliver of the total target audience. In this case, it's a highly profitable sliver.
Because it's more focused, it's easier to monetize. There aren't many places with this level of advice. You can pay for a subscription that lets you ask questions, read the articles, and get more information.
They also run their own BackpackingLight courses. They identified what people their audience wanted and charged for that.
If you get the concept right, everything else becomes far easier.