Why didn't they just fly to Ta Lo?

At the beginning, they show Xu Wenwu fly to his secret mountain compound on his helicopter. Then, when they decide to go to Ta Lo they... get in SUVs and drive through a bamboo forest? What?

The sky over the Ta Lo was wide open. The sky over the lake was wide open. The sky over the portal was wide open.

Even later in the movie when he is trying to get to the portal to save his "wife" because she's calling to him, he still doesn't fly there. Apparently, he can even use the power of the rings to fly himself from the village, over the lake, to the portal. But he can't manage to fly over some bamboo field in the mountains to get there? Really?