I pretty much only go to European games and about twice a year, as most of these games are 3-4 day long and normally +1500 people attending, it gives you more then enough experience to last you a half a year, till you need your next "fix"
Berget normally has anywhere between 3000 - 4000 people attending ( if I am correct )
BorderWar has anywhere between 2500 - 3500 people attending ( I go each year, so those figure are correct )
OverLoad is also run by some BorderWar crew, very well thought out game which is on the rise, they normally have 1500 people attending ( cheap game, but far away )
Pathfinder, went last year, interesting as it was set on a ex-military Island with a nice network of bunkers in Croatia, 400 - 500 people attended ( not many people attended, mostly because it was expensive to get there )
TeddyBhoy, in these games you can pretty much do anything you want, if you mean by foxhole that you want to be a sniper and dig your self in somewhere, then yes, I've heard of some snipers on these games that you see them at the beginning of a 4 day even, and then only see them again at the end of the game, they would sleep on the in-game field during the nights ( that's just a bit too much for me )
BorderWar is the closes which will be at the end of April, that's set near Prague, Ticket cost is about 70 Euros, I normally drive there as I have a in game vehicle I use, so that's about 150 Pounds one way, and plus the ferry crossing which is about 70 ponds both ways. Thats about 470 but that one person with a car, but if you go with more people then you can easily sprit the costs. A lot of people would fly, so about 90 pounds for the ticket there and back to Prague, hire a car for 4 days about 110 pounds and the game ticket 70 Euros, so about 250 pounds for a single person.
Berget which will be at the end of June is a bit further away, I am still planning that trip, it consist of a ferry from UK to Gothenburg, then from there a 8 hour drive, the 8 hour drive is not that bad on price, but the ferry ticket is a bit expensive, so still looking into some other solutions.