ALTADENA (CBSLA) – The trails at Eaton Canyon in Altadena have been closed for Memorial Day after they were hit with massive crowds over the weekend.

Cell phone video of large crowds at a waterfall in Eaton Canyon on May 23, 2020.

Eaton Canyon Natural Areas and Trails were shut down for a portion of Sunday and all of Monday due to “overwhelming crowds,” the Los Angeles County Department of Parks & Recreation announced.

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The parks department said it added trail monitors and horse-mounted patrols in anticipation of the busy weekend, but it was not enough. The closure includes all natural areas, the nature center and all trails. On Tuesday, the county announced that the closure would run through May 31.

Cell phone video from the Eaton Canyon waterfall Saturday showed a large crowd, many of whom were not wearing masks or physically distancing.

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“Despite these best efforts by the county, the large number of visitors to Eaton Canyon this weekend have made it evident that many people are not practicing key requirements and recommendations set forth by Public Health and supported by LA County Parks such as wearing face coverings, physical distancing and avoiding crowded areas,” the parks department said in a news release.

Earlier this month, L.A. County reopened trails during stage two of its coronavirus recovery plan, which also included reopening golf courses and tennis courts.

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On Friday, the county reopened parking lots at nearly all its state beaches and announced that retailers located inside indoor malls can reopen.