Rome Marathon (Italy, March)
It's no wonder that foreign runners make up more than a third of the field for this race, which is effectively a 26.2-mile sightseeing tour around the Eternal City. The race is held on a Sunday in March, and takes in the ancient splendours of the Colosseum, St Peter's Square, the Trevi Fountain, the Piazza Navona and the Spanish Steps.
And can there be a better destination for pre-race carb-loading than a city that lives on pasta, and has a trattoria on just about every corner?
THE COURSE Starting and finishing in the shadow of the 2,000-year-old Colosseum, the course is fairly flat for a city built on seven hills. But you're unlikely to improve your PB: conquering the cobbled streets that cover half the route will add minutes to your finish time.
FAST FACT For the first marathon of the millennium, organisers moved the start line to St Peter's Square, where Pope John Paul II blessed the runners.
Boston Marathon (USA, April)
In 1896, a team from the Boston Athletic Association took part in the first Olympics in Athens. Inspired by the "first" marathon, club members decided to organise a similar race the following year on Patriots' Day (the third Monday in April).
Today, Boston is the world's oldest continuously-run annual marathon. Since 1970, entrants have had to qualify for this prestigious race: the qualifying time is 3:10 for men and 3:40 for women aged 18-34, with graduated times for "masters" and "veterans", depending on age.
THE COURSE The field of 25,000 starts in Hopkinton to the west of Boston, and passes through several small towns before finishing in downtown Boston. All runners dread Heartbreak Hill: the 600m ascent between miles 20 and 21, but many consider the hill on Washington Street from the 16-mile point to be even tougher.
FAST FACT Every year, the Boston Red Sox baseball team plays a home game at Fenway Park to coincide with the marathon. After the game, the crowd cheers runners into the final mile.
Edinburgh Marathon (Scotland, May)
Only in its eighth year, this racein the Scottish capital has already earned a "must-do" reputation - consequently it's the second-largest UK marathon.
It's a fast course, with an overall descent of 40m -
so, great for PBs. And the organisers expect 15,000 entrants this year. Prefer to run a shorter race? The Hairy Haggis Team Relay splits the distance into legs for teams of four, and a whopping 19,500 entrants are expected to enter for this truncated test.
COURSE The mostly flat and scenic race starts in the city centre, taking in Holyrood Park, Leith Links and Portobello Promenade. It goes on to East Lothian to the coast, past picturesque fishing villages, before a grandstand finish at the Musselburgh Racecourse.
FAST FACT There's free entry for runners with proof of super-fast times: sub-2:40 for men and sub-3:00 for women.
Stockholm Marathon (Sweden, June)
Known as the "Venice of the North", situated across 14 islands on the edge of the Baltic, it's not surprising that Stockholm delivers a stunning 26.2-miler - many runners consider it the world's best. With a field of 20,000, half them foreigners, and boisterous crowds cheering on, this race has an amazing atmosphere.
And while most city marathons take place on a Sunday morning to minimise disruption, this event goes off without a hitch, despite starting at 2pm on a Saturday afternoon in early June. But beware the summer heat: the 2009 race saw temperatures of 30°C.
COURSE It involves two different loops of the city, starting outside the 1912 Olympic Stadium and finishing on the track inside. There are large, flat sections of the course, but enough undulations to break your rhythm. Beware of Västerbron (right): Sweden's largest arched bridge provides the toughest ascent of the race. And you'll have to do it - twice.
FAST FACT Stockholm Olympic Stadium was built for the 1912 Olympics and holds the world record for the most world records broken at one venue: currently 81.