A 246 kilometer race from Athens to Sparta to replicate the path that Pheidippides traveled in 490 BC to seek help in the war between the Greeks and the Persians before the battle of Marathon. According to the ancient Greek historian Herodotus, Pheidippides arrived in Sparta the day after his departure from Athens. Accordingly, there’s an aggressive 36 hour cutoff. Connie raced it in 2015. Ask her about it sometime.