Lothian Buses bus 506 (reg. T506 SSG). It's a 1999 built Dennis Trident/Plaxton President - numerically the very first of the type purchased by the Edinburgh operator. After seeing service in the standard fleet, it was later converted to a half-open topper and put to use as seen here, on the City Sightseeing tour, which Lothian runs in Edinburgh. It's seen here heading south, negotiating the curve on Horse Wynd, in the sightseeing rich area at the bottom of the Royal Mile. The Scottish Parliament is off to the left, <a href="//commons.wikimedia.org/wiki/Holyrood_Palace" title="Holyrood Palace">Holyrood Palace</a> is over to the right. Heading the other way is a single decker of the standard fleet, albeit one of the eco green liveried specially modified Dennis Dart SPDs - this one being No. 54 (SK52 OHX).
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/33205016@N05">Graham  Mitchell</a> from Darlington, UK
CC BY 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/grahammitchellphotography/5719183943/">IMG_1266</a>