Tourists are flocking to the key hill destinations in Himachal Pradesh to beat the scorching heat in the plains, with as many as 6,31,000 vehicles reaching Shimla in the past 24 days, including 70,000 in the last 72 hours, officials said.

With the summer tourist season yet to reach its peak, Shimla, the 'Queen of Hills', is already choked with vehicles, leading to frequent traffic jams and prompting police to make a special appeal to tourists to adhere to traffic rules and conduct themselves as responsible citizens.