The IU Natatorium on the campus of IUPUI — fondly referred to by its nickname, “The ‘Nat” — is one of those revered, hallowed cathedrals of sport. For decades, the Olympic Trials called The ‘Nat home. Every four years, the fastest swimmers in the country descended upon Indianapolis for these Trials, along with thousands of swim fans, myself — a young, aspiring age group swimmer — included, to cheer on their heroes and imagine their own selves one day qualifying for the Olympics.

What makes The ‘Nat so special? The names on the wall. The names of those Olympic qualifiers, painted above the diving well at the far end of the pool, grouped by Olympic year, so all can see. Names like Pablo Morales. Names like Jenny Thompson. Names like Dara Torres. Names like Eric Namesnik. Any swimmer with a heartbeat feels that drum pound a little harder, a litter faster, with a little more urgency.

This weekend, the TYR Pro Swim Series returns to this chlorinated institution, The ‘Nat. Not only is this one of the best venues in America to watch a swim meet… this will be one heck of a competition.

As always, here are your 5 Storylines…

1. Katie Ledecky tunes up.

She’s the most famous active swimmer in the world. This weekend, Katie Ledecky dives into the long course waters, a summer championship competition season awaiting. She’ll dominate the mile. She’ll maybe be pushed by Leah Smith in the 400 freestyle. It’ll be great to see her, if the psych sheet holds up, in the 100 freestyle and 400 IM, where there should be nice competition. Most of all, I’m excited to watch that 200 free. Allison Schmitt, 2012 Olympic gold medalist in this event, is scheduled to compete. There’s nothing I love watching more than two Olympic gold medalists swim side-by-side in the middle of a fast pool. Watch for early fireworks.

2. Another Stanford Cardinal, Simone Manuel, looks to dominate the sprint frees.

Stanford teammate Simone Manuel is also scheduled to compete this week in the sprint events. She’ll battle Ledecky, of course, in that 100 free. Mallory Comerford and Allison Schmitt will be right there as well. But the event I’m more interested in is that 50 freestyle. Manuel is a sprint phenom, and was just a few tenths of a second off that 50 free world record last summer. While that seems like an eternity in an event like the splash-and-dash 50, with a talent like Manuel, we could see that 2009 WR go down sooner than later.

3. The men’s 100 freestyle is a blast from the past — and it could also be a foreshadowing of the future.

I have fond memories of watching Gary Hall, Jr., qualify for the Olympic team in this very pool. There’s something epic about watching the 100 freestyle here, under those painted Olympic roster names, feeling like the older generations of swimmers who came before lurking around in these hallowed halls. The 100 freestyle is, to me, the event where legends are made. It determines relay anchors. It determines fastest swimmer down-and-back. It determines who will lead Team USA against the world. This weekend, I’m excited to see Olympic veterans battle in the 100 freestyle: Nathan Adrian, Matt Grevers, and Cullen Jones, legends in their own right, will all compete in this event. So many Olympic memories of watching each win Olympic gold. I’d love to see them all make the final, and compete in the middle of the pool, just like yesteryear.

4. Chase Kalisz in the 400 IM. .65 off US Open record.

While the 100 freestyle may be swimming’s glamor event, the 400 IM determines who really is the best all-around swimmer in the world. And recently, Chase Kalisz might win that argument. Last year, Kalisz took the swimming world by storm with some spectacular World Championship swims. Could he take down Michael Phelps’ US Open record? It certainly looks like he’s got an opportunity to later this summer — he’s seeded less than seven tenths of a second off. The 400 IM has been one of those American-dominated events internationally, until 2016 when Japan’s Kosuke Hagino snapped the USA’s Olympic gold streak in the event. Kalisz will look to return the title back to the USA in 2020… but first, he’s got to get through this weekend.

5. Carson Foster in the 200 backstroke.

One of the teenage phenoms to watch over the next few years is Carson Foster. He’s posting some of the fastest times in the country for his age group, and he’ll be looking to make a name for himself this summer. His best shot at making a podium this weekend could be the 200 backstroke. Foster, just 16 years-old, is seeded second in that event with a blistering 1:57. It’s easy to imagine him challenging for a Pan Pacific roster spot later this summer. Whenever the swimming season hits this mid-point marker between Olympics, fans always peek down the heat sheet to scan what up-and-coming names could make a splash come Trials Time. In the 200 backstroke, one doesn’t need to look very far to see what the future holds.

As always, tune into USASwimming.org throughout the TYR Pro Swim Series at Indianapolis for complete coverage, results, and live streams of the event!