when?
139/140-143-144 AD
Panathenaic Stadium
Tobin suggests that "Herodes built the stadium soon after [his father] Atticus's death, which occurred around A.D. 138. The first Greater Panathenaia following his father's demise was 139/40, and it is probable that at that time Herodes promised the refurbishment of the stadium. According to Philostratus, it was completed four years later, which would have been in 143/4." These dates (139/140-143-144 AD) are now widely cited as construction dates of the stadium of Herodes Atticus. Welch writes that the stadium was completed by 143, in time for Panathenaic festival.

who took part in the modern olympic games Fourteen nations; all European, and 241 athletes (all males) when was this? From 6 to 15 April 1896 where did it take place? Athens, Greece which were the venues? Panathenaic Stadium, Marathon, Bay of Zea, Zappeion, Kallithea, and Athens Lawn Tennis Club was there an opening ceremony conducted? Yes where? Panathenaic Stadium has it been used for any other purpose? Yes, hosted the opening ceremony of the 1997 World Championships in Athletics which other olympics have been held here? Zappas Olympics and 2004 Olympic was any reconstruction work done to it? Yes
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Panathenaic Stadium [SEP] Reconstruction by Herodes Atticus
One side of the throne includes a relief showing an olive tree and a table on which rests a Panathenaic amphora with the front leg in the form of an owl. According to Welch there is a possibility that criminals were executed in the stadium, however, no evidence exists. Herodes Atticus built it as "an architectural means of self-representation, and it did something analogous. The architecture of the building makes allusions to the Classical past while remaining unmistakably modern. It is Roman in scale, but it self-consciously rejects the distinguishingly Roman features of monumental facade and extensive vaulting." Its cavea was decorated with owls in relief, which symbolize Athena.