Ex 14:21-22
21 Then Moses stretched out his hand over the sea and GOD, with a terrific east wind all night long, made the sea go back. He made the sea dry ground. The seawaters split.
22 The Israelites walked through the sea on dry ground with the waters a wall to the right and to the left.

Another huge miracle but they were only focused on what they could see and they could see the Egyptians coming after them and that meant more to them than the fact that the ocean waters split.