Cuckoos

<spoiler> To find out the value for each textbox, click on the clock. The cuckoo will indicate the value. Do not fill in values for the faded out clocks yet.

Since the presentation in Las Vegas had two missing cuckoos, 3 and 7, enter 3 in the first faded clock and 7 in the second faded clock.

You will get back the following coordinates: 51°30'02.61"N 0°07'28.66W. The coordinates correspond with the Big Ben in London. Therefore, the answer is "Big Ben." </spoiler>