We invite our guests to dress to the nines. Tuxedos and formal gowns are more than encouraged for an evening of timeless elegance, celebration, and serious dancing. Glamour is required. Mobility is highly recommended!
See links for ideas:
https://www.brides.com/story/black-tie-wedding-guest-dress-code-long-gowns
https://www.theknot.com/content/what-to-wear-black-tie