Words to Describe amphitheaters

How amphitheaters often is described ("________ amphitheaters")

• broken
• cool
• glacial
• vast
• semicircular
• magnificent
• shady
• deep
• great
• outdoor
• natural
• permanent
• shaped
• huge
• surgical
• open
• later
• public
• scoured
• gigantic
• symmetric
• grand
• owned
• walled
• noble
• agricultural
• immense
• large
• numerous
• profound
• provincial
• largest
• greek
• oldest
• roman
• enormous
• ancient
• earlier
• broad