By Mitch Phillips LONDON (Reuters) - Callum Hawkins faces a huge test of his ability when he takes on Mo Farah in the inaugural 'Big-Half' race over 13.1 miles on the streets of London on Sunday but getting to the start line might prove an even bigger challenge for the talented Scot. Hawkins is desperate to go head-to-head with multi-world and Olympic track champion Farah in the half-marathon and on Friday embarked on what could be a long and arduous drive from Scotland on roads littered with abandoned cars due to the ice and snow that has caused such chaos in Britain this week. After failing to secure a flight over the last two days, Hawkins will be following in the tire tracks of compatriot Laura Muir, who also took to the roads via a 1,500 pounds (,065.50) taxi ride from Glasgow to win a bronze medal in the 3,000 meters at the world indoor championships in Birmingham on Thursday.