Obstacles to economic development include a lack of transportation infrastructure.
Obstacles on the way include large rocks and a canyon, both of which they got through with little trouble.
Obstacles on the ground include bottle caps and large ropes.
Other obstacles, he said, include the fact that corporate buyers "are generally older, and old ways die hard."
Other obstacles sometimes placed on the track include school buses and small airplanes.
The obstacles they face include language barriers, an unfamiliar working environment, family or cultural traditions, and so on.
But before they had gone very far, they encountered an obstacle not included in their plans.
The obstacles include the Republican leadership, which has been unable to agree on a strategy to pass this year's spending bills.
Obstacles to redevelopment may include lack of funding and increased scrutiny.
The obstacles here include the trade-off between fertility and longevity.