Billed as the “World’s Largest Squash Spectator Event,” the Tournament of Champions is back at Grand Central Terminal’s Vanderbilt Hall for the twenty-second year, consisting of squash matches and other related special events held in a specially installed ten-ton, four-walled glass court where you can either buy tickets for one of the coveted five hundred seats or just watch in a standing-room area for free. The women’s semifinals take place today at 5:00, with 2016 GCT champ Raneem El Welily from Egypt playing fourth-ranked New Zealander Joelle King, followed by two more Egyptians, reigning champ #2 Nour El Sherbini (who also won in 2016) battling it out with #3 Nour El Tayeb. The all-Egypt men’s semis begin at 8:00 with top-seeded 2015-16 champ Mohamed ElShorbagy taking on 2017 winner Karim Abdel Gawadat and #2 Ali Farag slugging it out with #4 Tarek Momen. The finals for both are set for Thursday night at 6:30. You need to get there very early if you want to watch without tickets.