Pointer: Looking for an open-source / free for personal use forum+CMS+gallery platform

Hi all,

Please have a look at https://www.experts-exchange.com/questions/22066927/Best-open-source-free-for-personal-use-forum-CMS-gallery-platform.html & post all replies there!
This question is worth 500 points, and the question is as below. PLEASE DON'T REPLY HERE!
Thanks

Original Q:
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A bunch of my friends have gotten together to form a group that is going to organise and conduct (for ourselves) various adventure / hiking / mountaneering / nature / culture trips over the next few years, at a rate of about 2/year.

I'm looking to set up a community website for the members of our group, which should have the following features:
* Some kind of showcase that will serve as the definitive repository for trip information, per trip. So one entry per expedition, with detailed itinerary, details of accommodation etc etc, that will be used as reference while planning, and as an archive after the expedition.
* Forum so that users can communicate with each other, we'll probable create a forum area for each trip, and sub-areas for separate discussions, including one for the organisers announcements, kit list, things to bring, things to see etc etc.
* Photo Gallery (moderated?) so that users can post photographs of the trips, and maybe with the facility to have 1 or more gallery admins who will be able to create albums, select photos from the ones that have been uploaded etc.

I'm sure I'll think of more things, but we're keen to get this up and running asap, so I thought I'd see what you all think. Obviously, any platform with better support, and better flexibility in terms of future changes / growth would be best, but also keep in mind that no one will be employed to run this, so it should have low overheads in terms of setup & maintenance!

I've seen / used / got a bit of experience with phpbb, smf, community server, joomla, gallery and a few others.

Hosting-wise my preference is to go *nix, and therefore php/mysql, but am open to switching if the reasons are compelling enough...

Looking forward to all opinions...

Cheers