To have a multiplicity of ethnic groups sharing a nation doesn't always make for easy politics.

But it makes for fascinating exploration.

On Monday, we caught the train from the station just five minutes' walk from our flat to Shah Alam. Here Malaysia's Malay heritage is well to the fore.

Most of the families strolling round the very pleasant lake area were Malay, and the people frolicking in Wet World were well covered up. We ate lunch at a Malay buffet place in the mall, choosing from the vast array of meats and vegetables prepared to accompany rice (the highlight was some lovely spicy tempeh -- I've not had that since Indonesia).

And Shah Alam, of course, is dominated by its gorgeous mosque. The plaintive sound of chanting accompanied us round the top end of the lake. And once prayers were over, we went inside. It's quiet and blue and beautiful. Impressively serene.

Yesterday, we took the train in the other direction -- to Batu Caves. It's Indian Malaysia that is predominant here.

The caves are an act in three parts, as it were.

First, you can toil up the steps to the huge caves that house the temples. As always, these Hindu places of worship are a riot of colour, which contrasts amazingly with the stark grandeur of the caves themselves. A group of Hindus was worshipping there, with drums and other percussion instruments, chanting and clapping. A steady stream of people were making offerings individually at the temples, assisted by bare-chested priests. (The far cave is infested by a rabble of macaques. Lawless as usual, but less of a nuisance than usual.)

Down at the bottom, there is the "Cave Villa". This is a riot of psychedelic colour -- painted caves, illuminated tableaux of brightly coloured gods, and a disco ball... There are other exotica, too, like snakes and peacocks.

And in the middle, there's the "Dark Cave". This space was provided with paths a few decades ago, but since then the lighting and other tourist infrastructure have been removed, and the emphasis has been put on conservation. Here there is darkness -- a darkness filled with bats and spiders and cockroaches and centipedes. It's quiet apart from the squeaking of the bats and the trickling of the water. There are the usual stalactites and stalagmites, and there is also an extraordinarly beautiful "flow stone" -- a huge, yellowish column, down which the water ripples in delicate little curly waves.

Before getting the train home, we had a late lunch at one of the Indian eateries just in front of the caves. A thali (rice with different curries and chutneys), vadas, and masala chai -- took us straight back to the subcontinent where we were not so long ago...

And today we went to KL's Chinatown. Here on full display is Malaysia's China vibe. We started with breakfast at Yut Kee kopitiam, a traditional Hainanese eatery. Pork porridge for me, ginger beef for Nigel. Great atmosphere.

Then a walk around historic shophouses, busy markets, and bustling temples where worshippers gathered to offer incense and other gifts.

We ended up at the Purple Cane Tea Restaurant, where we had fragrant oolong tea accompanied by little snacks -- light and delicate sweet potato steamed buns, and "pearl rice", which came wrapped up in leaves. Delish -- must go back for more...

This rainbow of ethnicities is also reflected every day in the faces and clothes of my colleagues at work, and of my fellow-passengers on the buses. I know it's not always easy to make this work. I know tolerance gets stretched at times, and patience wears thin. But multi-culturalism is so rich, so vibrant, so part of our humanity that I really pray the effort continues.