There is, of course, much to be said for the blockbuster art show, with glamorous paintings being jetted in from across the world — the supermodels of the art-world, if you like — for us to ogle. But while blockbusters often fill in a big gap, or are  blindingly wonderful, they are all too often just exhausting, both physically and mentally. You really have to be ready for them.

More often, something small but perfectly formed is what I want. Something wonderful, certainly, but not something that needs hours and hours of my time and energy. And Room 1 at the National Gallery has, reliably and dependably, for years now been the answer.

Room 1 is just up from the main entrance under the National Gallery’s portico, a single small-ish room, cut off from the rest of the museum because it has no other entrance: it is a destination, not on the way to somewhere. And it is the destination, cut off from blockbuster-dom, for small, eminently civilized shows.

Sometimes, as with the very splendid ‘The Making of a Spanish Polychrome’, Room 1 links in with a bigger show in the gallery (in that case, with the profoundly moving ‘The Sacred Made Real’, an exhibition of Spanish religious sculpture from the 17th century).

Sometimes they just show a rarity — say, Titian’s ‘Triumph of Love’, which had not been seen in public for half a century — with a few other pieces that link to it, or amplify its meanings.

And now, about to open, is a show on the American Ashcan school of early 20th century artists, another gem. As an introduction to a school of art almost unknown in Europe, this would be a useful show no matter what; but in fact, at least half of the dozen canvases are incredibly beautiful. And because it’s six, not sixty, they can all be appreciated.

Not every show in Room 1 is always first rate, of course. But the idea of the room, and the idea of the shows, are right: something bite-sized; miniature but carefully curated shows that we can look at, reflect on, consider.

Room 1 is a space in which to think. And those are rare enough to treasure.