Question:  Day of Days is a live album by a band who celebrated their 30th anniversary with an event at one of the largest and most important castles in what country?

Context paragraphs:
EMLL 30th Anniversary Show (1): Mexican professional wrestling promotion celebrated their 30th anniversary with two professional wrestling major shows centering on the anniversary date in early to mid September.  The first EMLL 30th Anniversary Show took place on September 6, 1963 in Arena México, Mexico City, Mexico to commemorated the anniversary of EMLL, which over time became the oldest professional wrestling promotion in the world.  The Anniversary show is EMLL's biggest show of the year, their Super Bowl event.

Arena Naucalpan 30th Anniversary Show: The Arena Naucalpan 30th Anniversary Show was a major annual professional wrestling event produced and scripted by the Mexican professional wrestling promotion International Wrestling Revolution Group (IWRG), which took place on December 20, 2007 in Arena Naucalpan, Naucalpan, State of Mexico, Mexico.  As the name implies the show celebrated the 30th Anniversary of the construction of Arena Naucalpan, IWRG's main venue in 1977.  The show is IWRG's longest running show, predating IWRG being founded in 1996 and is the fourth oldest, still held, annual show in professional wrestling.

CMLL 74th Anniversary Show: The CMLL 74th Anniversary Show was a professional wrestling major show event produced by Consejo Mundial de Lucha Libre (CMLL) that took place on September 28, 2007 in Arena México, Mexico City, Mexico.  The show consisted of six matches, with the main event being an "Infierno en el Ring" (Spanish for "Hell in the ring") Steel cage match, contested under "Lucha de Apuestas" rules, which mean the last man in the cage would be forced to unmask.  The participants risking their mask were: Atlantis, Blue Panther, Lizmark Jr., Místico, Perro Aguayo Jr., Dr. Wagner Jr., Último Guerrero and Villano V.  The event also featured five Six-man tag team matches, including an all-female match.  The event commemorated the 74th anniversary of CMLL, the oldest professional wrestling promotion.  in the world.  The anniversary show is CMLL's biggest show of the year, their Super Bowl event.  The 74th anniversary show was transmitted live on Pay-Per-View, something only a few anniversary shows before this one had been.

30th Anniversary Concert: 30th Anniversary Concert is a DVD release by Canadian hard rock band Helix.  It is a live concert recorded on July 17, 2004 at the Brantford, Ontario Sanderson Centre.  It is a complete concert and it features appearances from band members past and present to celebrate the 30th anniversary of the band.  The concert is interspersed with interviews, studio recordings and photo montages.

R30: 30th Anniversary Tour: The R30: 30th Anniversary Tour was a concert tour by Canadian rock band Rush that celebrated the 30th anniversary of the band's definitive formation in July 1974 after Neil Peart replaced original drummer John Rutsey.  It was also in support of the cover album "Feedback".  The tour started at the Starwood Amphitheatre in Nashville, Tennessee on May 26, 2004 and culminated at Sportpaleis Ahoy in Rotterdam, The Netherlands on October 1.  The show on September 24, 2004 at the Festhalle in Frankfurt, Germany was recorded and released as a DVD titled "" in November 2005.

Stirling Castle: Stirling Castle, located in Stirling, is one of the largest and most important castles in Scotland, both historically and architecturally.  The castle sits atop Castle Hill, an intrusive crag, which forms part of the Stirling Sill geological formation.  It is surrounded on three sides by steep cliffs, giving it a strong defensive position.  Its strategic location, guarding what was, until the 1890s, the farthest downstream crossing of the River Forth, has made it an important fortification from the earliest times.

30 Years Live: 30 Years Live is the 2nd live album from the band Bad Religion, which was released on May 18, 2010, therein documenting the band's 30th anniversary tour.  It is the band's first live album in 13 years, since "Tested" in 1997.  Rather than a standard release, it was available for free download to members of Bad Religion's official mailing list.

Day of Days (album): Day of Days is a live album by Scottish Celtic rock band Runrig.  The event at Stirling Castle celebrated their 30th anniversary, the band having been formed in 1973.

EMLL 30th Anniversary Show (2): Mexican professional wrestling promotion celebrated their 30th anniversary with two professional wrestling major shows centering on the anniversary date in early to mid September.  The second EMLL 30th Anniversary Show took place on September 27, 1963 in Arena México, Mexico City, Mexico to commemorated the anniversary of EMLL, which over time became the oldest professional wrestling promotion in the world.  The Anniversary show is EMLL's biggest show of the year, their Super Bowl event.

The 30th Anniversary Celebration: The 30th Anniversary Celebration is a live EP by the American heavy metal band Metallica.  The EP was recorded live on December 9 and 10, 2011 at Fillmore Theatre, San Francisco, California.  Metallica celebrated its 30th anniversary by playing four shows at the Fillmore in San Francisco.  The shows were exclusive only to Met Club members and tickets were only being charged at $6 (or 19.81 for all four nights).  The shows consisted of songs spanning their entire career and featured guest appearances by multiple artists that either helped or influenced Metallica.  These shows were notable for having Dave Mustaine, Jason Newsted, Glenn Danzig, Ozzy Osbourne, Jerry Cantrell, Rob Halford, Apocalyptica, members of Diamond Head, and King Diamond join Metallica on stage for all appropriate songs.

Supporting paragraphs: Day of Days (album) Stirling Castle
Answer: Scotland