Welcome!
The world is you oyster, but it's also huge and so can be difficult to narrow down exactly where to go.
It can help to ask questions to help narrow it down:
- Logistics: How far are you happy to travel to get 'there'? I tend to see travel time as mostly wasted, but if a longer plane flight might be the first for a number of you, it in itself may be part of the adventure.
- Daily activities. Do you value a vibrant and multinational / multicultural scene over seeing famous sites / sights? In short People or Places?
- City or nature... or a mix?
- Hot, Warm, Cool or Cold? This influences the places, but also the time of year, but perhaps the time of year is already set in stone? If so, that will help narrow down your choices.
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Outside of that, some additional thoughts:
- With 10 of you, be prepared to split up, ideally in different subsets, from activity to activity, but finding time to also meet up as a full 10 most days be that for breakfast, dinner, or a shared activity. Some might also value a little quiet time, so having flexibility in plans is ideal.
- Pre-holiday prep can be fun, but I'd also expect many to be disinterested in it, but happy to 'go with the flow'. For me prep serves the following purposes:
1) Helps keep the prospect of the holiday exciting, especially when set against the daily grind.
2) Heavily reduces the disorientation of a new place and that feeling of not having a clue what's near / good to do. It also helps avoid falling into the obvious, and especially the pitfall of eating in restaurants near a major landmark / tourist attraction, which are invariably rubbish and overpriced. This perhaps typified by advice for Venice which simplifies to "Get lost!" i.e. explore away from the main attractions / thoroughfares, in order to get better / more genuine experiences.
That prep might include having 'google streetviewed' the place where the airport bus drops off, having a map and already planned to route to where we're staying, options for day trips, restaurants, bars, shops, etc. etc. that I can tap into, but with the prep embedding some of it in my brain. It's an alternative to the idea that we resort to our mobile phones 'in the moment' and stop to seek its guidance.
- If going to a non-English speaking location, most popular destinations will have plenty of English speakers... but it's still great to make some sort of effort, if only to learn the basics of hello, numbers, thankyou, etc.