Indiana University Natatorium

After making do with the training pool last night, and with my hotel only five minutes away, head back to the Indiana University Indianapolis campus for the mid-morning competition pool session. That's after a power walk around Indianapolis in the blazing sun. Fingers crossed the guy on reception yesterday is right and they can slot me in!

Already know the way, so it's back into the visitor parking garage and straight to pool reception. Fortunately, it's the same guy and he remembers me! I'm allocated lane three, with an apology that I'll have to share with someone else for a short while.

Then through the doors and onto the magnificent pool deck. It is huge! Spectator seating runs down both sides of the 50m pool, with a separate Olympic diving facility at the far end of the hall. The near end is dominated by a huge digital scoreboard.

Quick change in the locker room, then head down to lane three. The pool hall is simply stunning. Large windows along the barn style roof flood the water with light, giving the whole place a bright, energetic feel.

What makes this place so special? The IU Natatorium is often described as the 'Yankee Stadium of swimming', and with good reason. It is the largest indoor aquatic facility in the United States, with seating for around 4,700 spectators, and one of the most famous competition pools in the world.

Across its history, the Nat has hosted 14 Olympic Trials covering swimming, diving and synchronised swimming. Some of the biggest names in aquatic sport have competed here, including Michael Phelps and Greg Louganis. By the Nat's own count, 138 American records and 22 world records have been set here.

One of its most distinctive features is the Olympic Wall behind the diving well. When an athlete officially qualifies for the U.S. Olympic team here, a calligrapher is lifted into position to write their name directly onto the wall. That's a fantastic tradition.

The building was designed with input from legendary Indiana University swimming coach James 'Doc' Counsilman and quickly became known for producing exceptionally fast racing. Aaron Peirsol is among the swimmers to set a world record here, with his 100m backstroke in 2009.

At 220,000 square feet, the venue includes an eight-lane 50m competition course, a separate six-lane 50m training pool and a full diving well. For today's lap swim, the main pool is set with ten lanes. It is a properly iconic place to swim.

The pool is fairly busy. The swimmer in my allocated lane is working through alternate-arm drills, and he is fast! Jump in, wait for him to see me, confirm we're circle swimming, then let him reach the far wall to create a decent gap before making a start.

The pool is built for speed. The temperature is perfect, the depth runs from nine to ten feet, and the water feels completely settled. The only thing missing from a typical competition setup today is the double wave-breaker lane ropes. It certainly has everything else. The starting blocks are top of the line, with all the integrated timing, lights and wiring. I would expect nothing less here!

I'm here for the experience today, and there's likely a second swim on the cards in Ohio, so it's 1km followed by a mix of 150s, 100s and 50s to bring me to a clean 1,600m, near enough a mile for today.

It sounds funny to say when you're only pushing a 1:30 pace for a steady 1,600m, but this really does feel like a super-fast pool. I think it's the deep water and the tiles on the pool floor. They somehow make it feel as though you're flying.

Swim done. Not sure I've ever given a pool full marks before, but this one deserves it! Is it better than the London Aquatics Centre?

Head into a slow warm-down to admire the pool one final time. Very pleased to have made it back and experienced this magnificent place. I can head into Ohio happy now!