MONTREAL, Canada - A truism of modern Formula 1 is that after Monte Carlo comes Montreal, with about the only similarity between the two circuits – apart from the first three letters in their respective names – being that each is in a French-speaking territories and bounded by water, in the latter case the St Lawrence Seaway in Canada’s Quebec region.For the rest, they could not be more different if they tried, for the Circuit Gilles Villeneuve, named after the late, great Canadian ace and father to 1997 champion Jacques (plus great friend and Ferrari team mate of Jody Scheckter), is on the Île Notre-Dame, an artificial island formed by 15-million tons of rock excavated for the city’s metro system and dumped in the enormous river.Watch the video!Indeed, the subway, which burrows beneath the waterway, provides circuit access for most of the 100 000 cheering and highly knowledgeable local fans who pack what was for many years the only GP on North American soil.FEW REMAINING CHALLENGESOf the current F1 calendar, the only other circuit named in honour of a former driver is the Autodromo José Carlos Pace, home of the Brazilian GP at Interlagos. Like Pace, Villeneuve was a GP winner on home soil.Read JULIAN LINDEN'S preview of the Canadian GPThe 4.36km semi-permanent circuit, bordered on one side by the 1976 Olympics rowing bowl and on the other by the 1967 Expo biosphere, resembles a distended oval with hairpin bends at each end. Its extended 320km/h straights are punctuated only by chicanes, with cars being on full throttle for 72% of each lap. The longest foot-flat stretch lasts 14 seconds – 19% of last year’s pole position-winning time. As such the circuit is one of the few remaining high-speed challenges on the trail, delivering lap averages of over 215km/h despite 11 of its 14 corners being taken below 160km/h, three of which are taken below 100km/h. Yet so fast is the overall circuit that last year’s pole lap time (1:13,8 minutes) was second-shortest of the season after Interlagos.A combination of capricious weather – rain is forecast for both Friday and Sunday, and likely to fall on Sunday – and unforgiving walls which hem the race track on all sides makes Canada one of the most exciting and unpredictable grands prix of the year, with a higher percentage of stoppages, incidents and safety cars than usual.TWO DRS ZONESIn fact, over the past 10 years there have been a total of 13 pace car phases in Montreal - including five in 2011, albeit none in 2012 – while three of the past four races here featured at least four leaders. The race has been won from pole three times in the past 10 years - compared to nine out of 10 at Monaco.The International Automobile Federation has specified two DRS zones but, uniquely, they will be activated by a single detection point 110m after turn nine. Activation 1 is 55m before turn 12 (Casino Straight) and Activation 2 70m after. Thus virtually the full length of the straight is available for low-drag overtaking, with the 60kW kers boost further spicing matters. The traction required to power out of slow and medium speed corners combined with low downforce chosen to facilitate optimum speed down the long straights places heavy demands on rear tyres, with fronts being punished by seven extremely heavy braking events per lap. Turn 1 is most dramatic of all: drivers slow from 300km/h to a fifth that in 100m/2.5 seconds as deceleration reaches 5.25g.'UTTERLY UNPREDICTABLE RACE'Then there is the infamous final turn (14), aka "Wall of Champions" on account of regularly catching former and current World champions. In 1999 Damon Hill, Michael Schumacher and Jacques Villeneuve crashed here - then bearing the slogan 'Welcome to Quebec' - while GP2 champion Nico Rosberg and former CART champion Juan-Pablo Montoya later fell victim. In 2011 it claimed Sebastian Vettel during Friday practice. The track’s surface is low-grip and rutted by the region's polar winters, causing cars to slide about and accelerate tyre wear. Following the current "Testgate" debacle, which resulted in both Ferrari and Mercedes being invited to answer accusations of illegal tyre testing, sole supplier Pirelli will make available for evaluation two sets of experimental tyres to each team on June 07 2013.However, for mainstream running, Pirelli has nominated its Supersoft (red sidewall) and Medium (white) compounds, a combination last used in Melbourne. The Italian company’s intention is that under dry conditions most drivers should stop three times, with the particularly gentle managing the 305km total race distance on two stops.All these factors point to an utterly unpredictable race, one which could well deliver a fifth winner this year after Kimi Raikkonen (Lotus, Australia), triple reigning champion Vettel (Red Bull Racing, Malaysia/Bahrain), Fernando Alonso (Ferrari, China/Spain) and Monaco winner Nico Rosberg (Mercedes).RED BULL IN THE LEADAny of the quartet plus 2012 winner Lewis Hamilton (Mercedes), who has won here the three times (2007, 2010, 2012), and Red BUll second-stringer Mark Webber are in with a chance. Then, wet-weather star Jenson Button, who won here in atrocious conditions in 2011, cannot be discounted should the going get slippery despite his current McLaren not being up to scratch under normal conditions.On the cards is a continuation of the ding-dong battle between the Briton and his aggressive Mexican team mate Sergio Perez (who, suggested the usually laid-back Räikkönen in Monaco, should be punched by somebody) while the rivalry between Force India twins Adrian Sutil and Paul di Resta, who between them have pushed this flamboyant team to a remarkable fifth (ahead of McLaren) on the Constructors’ log, is equally intriguing. After six (of 19) rounds only 21 points – less than a win - separate championship leader Vettel (107) from Raikkonen with Alonso third on 78, eight shy of the Finn’s 86. Red Bull continues to defend its Constructor’s title with 164 points to the 123 of Ferrari, followed by Lotus (112) and Mercedes (109).The 2013 Canadian GP on June 9 will start at 8pm local time with qualifying an hour earlier on June 8. The cancellation of the planned New Jersey GP means a three-week break until the 2013 British Grand Prix at Silverstone on June 30.Stay with Wheels24 for the 2013 Canadian Grand Prix weekend.