A tradition since 1967, the annual lighting of the Zilker Tree is one of the Austin's most popular and recognized events.It's not technically a tree but rather one of the original Moonlight Towers (Austin's first illumination system, way back in 1894, consisted of 31 carbon-arc lamps on 150 foot tall wrought iron poles). The Zilker Tree is constructed of 39 streamers which hold 3300 individual bulbs in a spiral design. There is also a large, double star comprised of 150 individual frosted bulbs.