Complex sentence: The expedition stopped at a point about 20 miles (30 km) north of present-day Omaha, at which point they first met with the Otoe, and had a council meeting with members of the tribal leadership on the west side of the Missouri River.
Split into simpler sentences: The expedition stopped at a point about 20 miles (30 km) north of present-day Omaha, at which point they first met with the Otoe. They had a council meeting with members of the tribal leadership on the west side of the Missouri River.