Some 41,000 people flocked to the national exhibition, Expo.02, on its first day, with the Neuchatel site pulling the most visitors.
Marketing director, Rainer Müller, said it had been an "ideal first day" for Expo.02.
The four "arteplages" - or floating platforms - that make up the exhibition in western Switzerland's "Three Lakes Region" drew 41,000 visitors on Wednesday.
Of those, some 13,000 attended the second version of the opening spectacle, first staged on Tuesday night.
The most popular site was Neuchatel, which pulled in 13,200 visitors, followed by Biel (11,600), Yverdon-les-Bains (8,700) and Murten (7,600).
Müller said an estimated 1.85 million tickets had been sold by Tuesday evening - 67,000 of which went on Tuesday alone.
He added that this was about 43 per cent of the total expected ticket sales for the five-month exhibition, which ends on October 20.
For the opening ceremony on Tuesday night, 15,000 spectators gathered at the four exhibition sites to watch hundreds of actors, musicians, singers, swimmers and acrobats enact a two-hour extravaganza.
Based on Greek mythology, the three-act performances - staged simultaneously at the four sites - wove in Swiss themes, languages and music, often to the confusion of the audience.
The shows, put together by Swiss director François Rochaix, opened at dusk under a cloudless sky with the arrival of the mythical winged horse Pegasus, before a hymn to the night was sung and broadcast simultaneously on all four platforms.
Jet screams across the skies
Spectators then heard the sudden roar of an FA/18 jet swooping over their heads, marking the start of the separate shows in the four different locations across western Switzerland's "Three Lakes Region".
There were moments of theatrical and musical splendour on the lakeside platforms, but there were also moments of thematic incoherence that left the audience grappling with their programme notes in an effort to make sense of show.
Audience response was mostly positive but grew more muted as the shows wore on. Expo's organisers are hoping however that the five-month exhibition proves more of a success.