The Amphitheatre, facing south on the hill north of the site, was completed for the opening of the first assembly on July 17, 1883. Built under the supervision of William Webster, landscape engineer of Rochester, New York, who came to Monteagle on November 1, 1882, drew the plans for the Monteagle Sunday School Assembly, and remained through the initial season as its first General Manager, it could seat nearly 2,000 people and accommodate a choir of more than 100 voices. Modeled after the Grand Opera House in Paris, it was built of rough lumber with rustic posts made from trees cut on the grounds with the bark left on them. The Amphitheatre was the center of church school and most general activity until it was razed in 1900 to make way for a new auditorium. The spring at Moses Rock was one of several springs that first supplied water for the Assembly, and the Pavilion next to Moses Rock was erected in 1904 by the Ladies Association, now the Monteagle Woman's Association, at the same time as the restoration of the spring after its streams had been blocked by dynamiting in a failed effort to increase its volume of water.