From the old to the new

When I realised I'd be in London the day before Open House weekend, I went onto the website to decide what to see. Overwhelmed. Tried again. Overwhelmed. So I went to the only section of the website that was simple - the page to enter ballots to see the most popular buildings. I entered every ballot and forgot about it.

I was astounded to get an email to say I'd won a visit this morning to the Bloomberg Building in the City.

Our guide was one of the Foster architects who worked on the building and we had at least three architects in the group asking interesting questions though she declared mine a little too engineeringy. As well as being an acclaimed environmentally-friendly building (it has no heating; it doesn't need it) it is beautiful. This is the view from the only meeting room that is not open plan (for clients who don't value open space as much as Bloomberg does) and in extras is an interior and an exterior. Another interior here.

The architects, one other photographer and I kept on slowing our group down until the next group, supposedly 15 minutes behind us, caught up.

Photographer and I, in a bit of a daze, then went into St Stephens Walbrook, right opposite, whose Wren-designed dome was allegedly a try-out for St Paul's. Although it's now dwarfed by city buildings, it holds its own and light pours in.

Under the Bloomberg building is the Temple of Mithras so I ducked underground for an insight into a weird male cult from 1,800 years ago.

Then I emerged to a shiny blue and gold day and spent the rest of it on the South Bank basking and talking with my mum.