Assertion: park's portion | /r/HasProperty | put in wooden box
Facets:
value: underground
type: LOCATION
value: due to sanitary concerns
type: CAUSE
value: before the 1904 world's fair
type: TEMPORAL
Source sentences:
text: At one time the River des Peres ran openly through the park, but due to sanitary concerns, a portion was put underground in a wooden box shortly before the 1904 World's Fair.