Panda Cub Bei Bei Takes First Steps Outside

— -- It was another milestone day in the life of one of America's favorite baby bears: Bei Bei's first time outside.

The Smithsonian National Zoo released this adorable video of the giant panda cub today. Bei Bei stuck close to mother Mei Xiang’s side as he explored the outdoor part of the zoo’s panda habitat.

The 5 1/2-month-old cub spent most his time attempting to climb a tree. Bei Bei and mom headed back inside after about an hour of playtime.