The city's highest observation deck is celebrating its first anniversary with free admission.

Next Tuesday, May 24, One World Observatory will waive its usual entry fee (tickets start at $32) between 9 and 11:30 a.m., giving out a limited number of free passes (two per person) online only beginning at noon today, May 18.

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The observation deck is the highest in the city, occupying floors 100-102 of One World Trade with 360-degree views of the city, New York Harbor and New Jersey. It opened on May 29, 2015.