If platypuses keep their eyes closed under water how do they find their burrow?

Platypuses dig burrows in the banks of the freshwater creeks, rivers or lakes where they do their hunting. The entrances are disguised beneath overhangs, or by tree roots and other vegetation.

Platypuses have webbed feet with retractable webbing which enables them to dig their burrows. Burrows can be over 30m in length (100 feet). During breeding season, the female digs a chamber at the end of a burrow, which is where she incubates her eggs.