Passage: The bowl-shaped stadium contains a continuous single tier of seats with a second tier on the west side. Its current capacity is 25,400. The stadium hosts two tenants, association football club Hull City A.F.C., which moved there from Boothferry Park, and rugby league football club Hull FC, relocated from the Boulevard. It is also the 2nd largest rugby league stadium in England. The ground also hosts international association football and rugby league football competitions and acts as a venue for concerts by musical artists, such as Elton John and The Who.

Question: What are two concerts that have been held at the stadium?
Elton John and The Who