Tripologist: Is 6½ months passport validity enough for entry to the US?

We're a couple travelling to the USA in mid-July and our passports are valid for 6½ months after we depart. We return a month later, is this a problem? I don't want to renew since the waiting time is many weeks. A. Lester, Chatswood NSW

You could well find yourselves in difficulty. Your passport must be valid for six months beyond the date of travel. You might even be barred from boarding your flight out of Australia since some airlines insist your passport must be valid for six months after your date of return. You can renew your passport in just two business days with priority processing. Make sure you follow all the guidelines for paperwork, documents and photographs when submitting your application. The additional fee is a stiff $225 but that's your best option, otherwise your trip might not get off the ground.

My husband and I want to see the autumn foliage in New England, USA, but where to go and should we take a tour or self-drive? C. Lackey, Geelong VIC

Most parts of New England deliver the molten colours you're looking for, although some places do it better than others. Essential elements include covered bridges, white timber churches with pointy spires, rolling hills and foaming rivers and that puts the state of Vermont, New Hampshire's Kancamagus Highway, Maine Coastal Route 1 and the Berkshire hills of western Massachusetts in the spotlight. Trafalgar [www.trafalgar.com], Cosmos [www.cosmostours.com.au], Insight [www.insightvacations.com] and Tauck [www.tauck.com.au] are some of the operators that offer autumn foliage tours.

I'll be attending a conference in Lisbon for 4 days in September, with four days before and two days after to explore. What can we do during this time, as hoping to see more than just Lisbon? H. Lin, Gladesville NSW

In your four-day break, you might take a train a short distance north to Nazare. The beach here is one of Portugal's finest and seafood is a specialty. Use this as a base to explore Obidos, a fortified town with narrow, cobbled laneways spiralling down from its hilltop castle, and perhaps the pilgrimage site of Fatima. Head north again to Porto and base yourselves in the historic Rebeira district along the waterfront. Explore Rebeira and the amazing Palscio da Bolsa, the former stock exchange, the church of St Francis and the riverfront promenade of the Vila Nova de Gaia neighbourhood, and perhaps sample some of the port wines for which the city is famous. The trip along the steeply terraced hillsides of the Douro River, the home of port, is an absolute must. Several operators offer cruises upstream from Porto to Pinhao, with a train ride back to Porto [www.cruzeiros-douro.pt]. In your two-day break, take in the narrow streets of Lisbon's Alfama district, the waterfront Belem area and a cruise on the Tagus River. You might also visit nearby Sintra, a beautiful town on the UNESCO World Heritage list, and easily accessible by train.

We're spending four days in Zurich in September, is it possible to squeeze the journey aboard the Bernina Express into a single day? P. Cavanaugh, Docklands VIC

Not without an exhausting day. The Bernina Express runs from Chur to Tirano, on the Italian/Swiss border, but by far the most interesting part of the journey is from St Moritz to Tirano, when the train rises through the Engadin Valley, crosses the Swiss Alps and travels down the Poschiavo Valley. To get to St Moritz from Zurich takes at least three hours and while the Bernina Express ride from there to Tirano is just over two hours, the return journey from Tirano to Zurich will take another five hours at least.

What you might do instead is take the 40-minute train ride from Zurich to Lucerne and hop aboard one of the belle epoque paddle steamers for the trip across Lake Lucerne [lakelucerne.ch/en/]. The lake is probably Switzerland's prettiest, cradled by forests that rise into bald mountains, its foreshores discreetly dotted with the mansions of the rich and famous. Don't stint – pay the extra charge for a passage on the upper deck, get a table outside and enjoy a leisurely lunch with the wind ruffling your hair. The trip ends at Fluelen, from where the train will whisk you back to Zurich in just over an hour.

Got a travel question? Include your name and suburb or town and send it to Michael Gebicki - tripologist@traveller.com.au

Travel advice is general; readers should consider their personal circumstances.