1) Ancient race tracks 2) Ancient running tracks 3) Arenas 4) Ballparks 5) Baseball parks 6) Big event sites 7) Bowl game sites 8) Bowl locales 9) Bowl settings 10) Bowl-game locales 11) Bowls 12) Coloseums 13) Colosseum et al 14) Elliptical buildings 15) FedEx Field and Fenway Park 16) Football sites Found on https://www.crosswordclues.com/clue/stadia
a method of surveying in which distances are read by noting the interval on a graduated rod intercepted by two parallel cross hairsmounted in the telescope of a surveying instrument, the rod being placed at one end of the distance to be measured and the surveying instrument at the other. Found on https://www.infoplease.com/dictionary/stadia