In mid-August we used our hire car for a 2-day visit to Sofia, accompanied by Martin & Shirley Jeffes. Previously we had only skirted Bulgaria's capital on the Ring Road, so it was a good chance to explore the city, home to 1.5 million people (over 10% of the population). Inhabited since Neolithic times, it's Europe's highest capital at 545 m (1,800 ft), making it pleasantly cooler than the sun-baked Thracian Plain.

The 270 km (170 mile) drive from Biser to Sofia took a steady 4 hours. The E80 via Harmanli and Haskovo to Plovdiv parallels the railway along the Maritsa Valley. It's a slow road, too narrow for the heavy traffic it carries to and from Turkey, especially in summer. Progress was much smoother once we joined the 'Trakia (Thracian) Highway' – the motorway from Plovdiv to Sofia - with a lunch break at the Happy Bar & Grill at a Shell services on the way.

Entering the heart of the city, we appreciated Martin's knowledge. He directed us past the huge St Aleksandir Nevski Church, the brightly tiled and gilded St Nikolai Russian Church, the National Art Gallery with sculpture-decked roof, the Party House (a Stalinist relic) and the Presidential Residence, complete with its pair of sentries. Traffic was slow but we kept moving until we met a protest march in the central St Nedelya Square, demanding the resignation of the President and Government (which seemed a bit over-ambitious!)

We went directly to our elegant little hotel, the Maria Luisa on Blvd Maria Luisa, about 1 km north of the Square (www.marialuisa-bg.com). A double room (en-suite, TV and fridge) cost €80 for two, including a generous breakfast buffet. With the car safely stowed in the nearby indoor car park (15 leva or €7.50 for 24 hours), we were well placed to explore on foot.

The renovated pre-World-War-I Central Market Hall, the Hali, was just along from the hotel. Its glass roof, supported on cast iron pillars, overlooks 2 storeys of stalls and cafes: a good place for a cup of coffee while people-watching. An outdoor market fills the narrow lanes behind the Hali, around the restored Sofia Synagogue/Museum, while over the road from the Hali lies the 16thC Banya Bashi Mosque.

The Mosque was open but, as we removed our shoes to admire the interior, the way was immediately blocked by a man demanding an entrance fee. Even the stunning mosques of Edirne and Istanbul are freely open to all (with a discreet box for Contributions) so we left Banya Bashi unseen. Barry, admonished for placing a shoe on the carpet in the doorway during these discussions, drew on his recent reading of Richard Dawkins to denounce this as superstitious nonsense! Which it is.

A pedestrian subway below Blvd Maria Luisa gives access to Sofia's new metro system, and also to a subterranean plaza with the weathered 14thC St Petka Samardjiiska Church (closed for restoration), its roof poking above street level. In another underpass we saw the substantial remains of the eastern gateway to Roman Serdica, with courses of later Byzantine and medieval brickwork in the defensive towers.

Walking into the city centre, past the Archaeological Museum and the Palace of Justice, we found Ul Graf Ignatiev, a street of new and second-hand book stalls, but only bought the excellent weekly English language paper, the Sofia Echo.

Shirley's birthday was celebrated with a splendid meal at the Steak House Restaurant (unique in Sofia for its steaks, and handily placed round the corner from our hotel). The balmy evening was completed with a moonlit stroll round the quiet centre. Our impression was of an orderly grid pattern of tree-lined boulevards, downtown streets with pavement cafes, bright new shops and fine National Revival public buildings, contrasting with the peeling stucco of dilapidated late 19th century properties still awaiting restoration. We felt quite safe and, though not lovers of large cities, we did like Sofia.

Next morning Shirley took a taxi to the Airport to visit family in the UK, leaving us to enjoy a lengthy hotel breakfast with Martin (food which kept us going until late afternoon!) We began to walk it off by browsing the popular outdoor market, then the flea market in Aleksandir Nevski Square in front of the Church, offering everything from old shoes to Russian medals and Roman coins! We paid our respects in the Church - completed in 1912 as a massive and impressive memorial to the 200,000 Russian soldiers lost in the war for Bulgaria's independence in 1877 - before having coffee in the adjacent park.

By chance, we passed the Presidential Residence on the hour, to witness the goose-stepping performance of the changing of the guard. Another good find was the wonderful Orange Bookshop on Graf Ignatiev: 3 storeys of stationery, disks and, of course, books. There was a wide choice in English, just charging the cover price (not doubling it, as in the bookshops of Athens!) and we left with a heavy bag.

The next couple of hours were spent in the Archaeological Museum, the oldest in the country, sited inside the restored 'Big Mosque' which dates from 1494. A superb collection of artefacts and sculptures from around the country, covering 3,000 years of Thracian and Roman history, was housed on 2 floors, though they needed more imaginative display to interest the public at large. We had the place to ourselves, apart from one elderly American tourist - perhaps the 10 leva (€5) entry fee helped to keep the numbers down.

Sofia's past reflects the history of Bulgaria. The first inhabitants were the Thracian Serdi tribe; the Romans called the town Serdica; the Slavs renamed it Sredets (meaning 'Middle' of the Balkans) and the Byzantine name was Triaditsa. During the Second Bulgarian Empire, around 1300 AD, its name finally became Sofia (Greek for 'Wisdom'), after the 6thC Church of St Sofia which still stands. Captured by the Ottomans in 1382 (and held for 5 centuries), it became the official capital of Bulgaria a year after its liberation in 1879.

Having, we realise, only scratched the surface of this Capital City, we left in the late afternoon to drive back to Biser, breaking the journey once again for a meal at the Happy Bar & Grill, just before Plovdiv. Should we return to Sofia, a priority will be the National History Museum, inside a former government palace in the suburb of Boyana, 7 km SW of the city centre.