Last Night's TV: Dan Cruickshank's Adventures in Architecture, BBC2<br />Natural World, BBC2

The titles for Dan Cruickshank's Adventures in Architecture present the series as one of those brightly coloured pop-up books aimed at the geographically minded child. As a silhouette of the presenter wanders around, pyramids and pagodas, porticos and onion domes magically fold up into place. And then you see a giant map of the world on to which the forthcoming attraction is passed like a part-work sticker. You get a little action figure thrown in for free, too, a kind of genteel Indiana Jones, complete with Panama hat and cravat, moveable eyebrows and arms that can be posed in a number of emphatic gestures. And if you press the right button, he says, "Golly!"

Endearingly, pretty much everything Cruickshank encounters seems to press the button. The "Golly!" count wasn't quite as high this week, when he was exploring the architecture of death, as it was in last week's opener, when the architectural miscellany was loosely held together by the idea of beauty. But we got one "Golly!" when he was negotiating the entrance shaft of Hatshetsup's tomb in Luxor and another one when he walked into the Sedlec chapel in the Czech Republic, in which a passion for Baroque furbelows has been expressed solely through the medium of human bones. Imagine a child's construction toy in which all the components have been replaced by bits of skeleton and you'll get some sense of the effect.

I think anyone might have said "Golly!" when confronted with Sedlec, to be fair, particularly when they spotted the Schwarzenberg coat of arms, made out of hundreds of skeletal spare parts, including the tasteful detail of a Turk's head having its eyes pecked out by a bony raven, or the rococo chandelier constructed from femurs and skulls. I wasn't entirely sure what it had to do with architecture as such – rather than a macabre take on interior decor – but then the series as a whole is more travel programme than architectural monograph. You're not going to get a lot about classical orders and Palladian proportions here. This is the world as wunderkammer, with Cruickshank tugging you around as the collection's wildly enthusiastic curator.

He brings an oddly chameleon piety to the affair, talking throughout in a reverent whisper that suggests semi-religious transport, with the veneration taking on whatever the background colour of faith happens to be. In a Buddhist temple, he sounded like a Buddhist, and in front of a wall relief of Hatshetsup, he talked quiveringly about her continuing presence in the afterlife and lit a bowl of myrhh as a tribute to her spirit. Obviously, there were limits to how far he could go in re-enacting the Mayans' equivalent of evensong, which involved ripping the beating heart out of a member of the congregation and chucking the body down the temple steps, but his account of the ceremony, delivered from a pyramid-top in the Guatamalan jungle, was so intensely charged that you could almost see the blood on his hands.

He finished in a place where the characteristic genuflection of his voice actually seemed to make sense: one of the dying houses of Varanasi, where devout Hindus come hoping for a fast-track to enlightenment. Oddly, though, his Western instinct of decorum – talking in hushed tones when ushered into a room where an old lady lay on her deathbed and murmuring about the privilege of being admitted at this private moment – collided with a placid local indifference to such concerns. As a confused calf was led into the room for a blessing, what I took to be the woman's grandson heaved her comatose body upright so that she could participate in the ceremony, worked by her loving family like a puppet. On the nearby burning ghats, the bodies of the recently deceased were stacked amid the firewood while tourists snapped pictures and mourners chattered and watched the bonfire. A set of scorched toes, topped by a low flame like some kind of novelty candle, protruded from the fire. Cruickshank appeared to have forgotten about architecture altogether by this point, but I think most viewers would have, too, so it didn't really matter.

In Natural World, we followed the annual migration of the reindeer herds with two Sami girls, Ella and her cousin Inge. Apparently, you don't ask a Sami how many reindeer he or she owns, as it's impolite, but it looked as if Ella's dad was rolling in reindeer, and watching his capital walk through the mountains of northern Norway to its summer grazing ground was astoundingly lovely. I usually get a bit twitchy when confronted with elegiac accounts of the immemorial traditions of ancient people, but the Sami appear unfussy about mixing ancient and modern, rounding up the reindeer with quad bikes and cataloguing their unique owners' earmarks on the internet. I'd prefer the silence to the quad bike, but then I don't have to climb a mountain to check the balance on my current account.