The worst i've experienced and hopefully last was at Keighley vs. Hull late 90's i think. The Hull fans weren't too happy throughout the first half, which resulted in the crowd surging forward and knocking down the sponsor barriers. They calmed down in the second half if i remember rightly after repeated warnings over the tannoy.

I can agree with JonM about the premiership semi. There were skirmishes in Widnes before the game and running battles inside the ground before half time.

It was at half time when things really went off when the Warrington fans went onto the pitch to change ends. Widnes fans who had been 'charged' out of the cowsheds had moved around the side of the ground and got onto the pitch from the terraces next to the main stand and met with Warrington fans on the pitch. What ensued really was a pitch battle with sets of fans from all sides of the ground spilling onto the field fighting went on for some time with the testart being delayed for 15 - 20 mins. Trouble continued through the town after the game.

The catalyst for the trouble was an incident in Warrington town centre after 'The Roller Rink' - anyone remember that? There had also been trouble for a few weeks before in and around 'the rink' and word had spread that Widnes lads shouldn't go on a certain Friday night as Warrington lads were to be there en masse. It was true as when us Widnes lads were making our way back to Central Station under police escort, Warrington lads 'en masse' as had been promised poured out of The Golden Square area and ran at us. The coppers even said the best thing to do was run for it.
One Widnes lad got stabbed twice - he was ok - I saw him on Saturday night just gone! A certain person who was at the time an Everton hooligan from Widnes arranged for his 'friends' from Everton to come over for the Premiership semi final promising that there would be little in the way of police and they could do practically what they want. Rumour has it that some Warrington fans were slashed on the pitch but I'm unsure how true this is.

I wasn't involved in any of the trouble as I too am a lover not a fighter, I was just a Widnes fan and a Roller Rink fan ( or at least the girls who used to go there).

Lots of little scuffles mainly with Cas, Fev and Leeds in the 80's/90's. But the Warrington prem semi was as bad as it gets.

By `88 CCTV, and by some degree the police, had both started to get there act together and the Aciiiiiiiiid culture was just kicking in. But for no explanation that I can give, there was very little police presence at RL in the late 70`s early 80`s (81-85 was very active what I can remember). Cages at grounds meant nothing, a lot of trouble happened outside of grounds. I have personally seen scores of incidents, a lot of them nasty. And thankfully not that I know of nobody has been killed at a RL game And let`s hope it stays that way.
As for the most large scale I`ll throw in Maine Rd 89
Burndem Park 87
And by the way, just because you didn`t see it doesn`t mean it didn`t happen.

think it was a play off game in 1996 got beat 41-28