Budapest Diary: Budapest looks fine in the spring sunshine. Pest, the eastern side of the city, is dominated by four- and five-storey buildings that have a subdued imperial air about them. Many of the buildings are divided into apartments, the sort of places built originally, one imagines, for middle-class merchants and professionals.
Andrassy Boulevard slices through Pest and is one of those anchor roads that serves as a point of reference for journeys across the city. A destination is frequently described as off Andrassy, or at the other end of it, or a mile or two south of it. That sort of thing.
Andrassy itself is very splendid. Perfectly straight, it rolls along for at least two kilometres, coming to rest at the Millennium monument and the Archangel Gabriel column in Heroes' Square. Andrassy is the sort of boulevard that signifies Budapest is a city with something to say about itself.
It has great girth - two lanes in either direction plus parking on both sides and fat, plane-tree-lined pavements. It is home to the Opera House and a few other grand buildings.
But the most arresting point along Andrassy is No 60: a four-storey-over-basement corner building that ought to be home to a bank or a very classy retail store; Versace, perhaps, or one of those minimalist kitchen shops. But No 60 is none of these.
No 60 is the House of Terror, a memory of the horrors inflicted on the people of Hungary between the 1940s and the collapse of communism there in 1989. It is the best, certainly the most disturbing but best-thought-out, museum I have ever been to.
The House of Terror stands out from all those buildings around it. It is painted a dull grey from top to bottom - the walls, the window frames, even the glass, all are painted grey.
A protruding vertical ledge, like the side end of a bookcase, runs up the facade of the building at either end. At the top, the ledge turns and continues across the top of the building, sticking out about six feet over the pavement.
This upper ledge casts a shadow down the facade of the upper floor. And like a giant stencil, letters have been cut out of the upper ledge. They are in mirror image and so, looking up from the ground, it is quite difficult to make out what they spell.
Except when the sun shines. When the sun shines, light falls through the cut-outs and on to the facade, spelling out a word in huge letters: TERROR.
Inside, the House of Terror tells the story of what happened to Hungary, and Budapest in particular, during the mercifully brief (October 1944 to February/March 1945) rule by the Arrowcross Party, an extremely bad, not to say mad, Hungarian fascist organisation, and the much longer communist era - equally bad and mad.
The merging of fascist and communist terror into one seamless horror is totally justified: No 60 was the Arrowcross HQ, and in its basement hundreds of people were tortured and murdered.
After the war, when Hungary became a client state of the Soviet Union, No 60 became the HQ of the Orwellian Department for Political Police. The torture and murder simply continued but in the name of a different ideology.
Most of the 19th-century buildings of Budapest face on to the street, behind which the building expands around a square courtyard. In the House of Terror, this courtyard has a glass roof and has been turned into an atrium.
An olive-drab and dust-covered Russian tank sits in the middle of the atrium. It has been placed in a vast pool of jet-black oil which rises about four incles up its tracks. The oil oozes silently out of the tank's belly and slithers gently down the steel plinth upon which the tank sits. Out of sight, the oil is pumped back into the tank, only to pour out again in a never-ending bleed.
As you buy your ticket and pass the turnstile into the former courtyard, the tank hits you like a ton of bricks: it is totally sinister, threatening and evil-looking. Up the wall on one entire side of the atrium and etched on to polished stone are hundreds of faces of the dead of 60 Andrassy Boulevard.
The tank is just one of several exhibits that stop you dead in your tracks. Another is the Russian Zil car, the sort that ferried notables of the communist regime across the city at great speed.
It stands in the centre of a darkened room shrouded in black muslin netting (the material used to keep mosquitos away from beds in the tropics) draped from ceiling to floor. The front wheels of the Zil are raised a few inches off the floor as though the vehicle is about to take off.
Every 20 seconds or so, lights inside the vehicle glow on, revealing plush red velvet seat coverings and cushions emblazoned with communist motifs such as stars, and hammers and sickles.
The scene is both funereal and threatening: the half-hidden world of the commissar bully, whooshing along the streets utterly removed from the people who his rhetoric proclaims are the real rulers.
The museum tells the story of Hungary's Jews: how over 60,000 were murdered in the Holocaust, how 30,000 were saved, some by Raoul Wallenberg, the Swedish diplomat who is one of the 20th century's true heroes.
It tells how over 700,000 Hungarians were removed into Stalin's gulags, 300,000 of whom vanished for ever. It tells how democracy was strangled by the communists in the late 1940s, of the misery of life in the 1950s, of the heroism of the 1956 revolt and the despair when it was crushed by Russian tanks.
And in the basement, where something still smells, it tells the story of the people taken there by the secret police to be beaten and hanged, strung up on posts standing mute now, keeping to themselves the stories and screams of those butchered because the end justified the means.
The House of Terror is open Tuesday to Sunday from 10 a.m. to 6 p.m. Admission is 3,000 forints (about €13). www.houseofterror.hu