The The grid is a reference to the starting order of the race is typically determined by qualifying, however, with the... There's more... walk occurs between the grid opening and the cars leaving for the The formation lap in F1, also known as the warmup lap, is the slow lap drivers take before the start... There's more.... Dignitaries, celebrities, team members and media have access to the grid to move amongst the cars and drivers.
A former F1 driver having driven for nine seasons. Martin now applies his vast knowledge and many entertaining one-liners to... There's more..., Sky Sports, has a segment called the Grid Walk where he wanders through the crowd identifying and talking to anyone of note. And it would be fair to say, that anything can happen and it often does.
Ther are other times that the grid is open to certain ticket holders to walk from one end to the other, but this is well outside the hours that teams have access to the grid.