114 players - including numerous Grandmasters and other titled players - are battling it out. Today they will have to battle even harder as they have to play two games.
Six players have a maximum score after the first three rounds.
Top pairings for round four
IM Gavin Crawley v GM Jon Ludvig Hammer
GM Mark Hebden v IM Graeme Buckley
IM Eirik Gullaksen v GM Niel McDonald
Former British Champions Michael Hennigan, Stuart Conquest and Robert Bellin are also in the thick of the action.
The Women's Invitational tournament is also a very competitive event.
WIM Arlette Van Weersel has started very well and currently leads the tournament with two and a half points from three games.
WIM Arianne Caoili and WIM Denise Frick are in joint second place with two points.
IM Susan Lalic, the tournament favourite, is close behind and has a game in hand (to be played on Sunday).
The percentage of draws is very low. Indeed, all three draws have occurred in the games of Elena Winkelmann, although they were not colourless games.
Pop along to the download page on the official site to catch up with the games.