The best ones are in the evening (which you have to pay for), but there also plenty of free ones which they hold at lunchtime a couple of times each week. They usually start at 1 PM, so it's a nice way to rest your feet if you've been pounding the pavement all morning. They've got a big cafe in the Crypt as well, where you can treat yourself to a cup of tea afterwards.
The free concerts can be anything from solo pianists to string quartets, and frequently include a vocalist or choral group -- it's all top quality stuff, and well worth a visit. Check out their website to see exactly who's playing. They usually perform works by the likes of Mozart, Handel, Bach and Vivaldi.
Craig has never been to one of these classical concerts, but he has written a review of St Martin in the Fields church. You might like to give it a quick read before you go, to see what they church is like inside.
There are plenty of other attractions within a short walk of the church. After you've rested up maybe you can pop in to the National Gallery next door? Or have a walk down Whitehall to see Number 10 Downing Street, Big Ben and the Houses of Parliament.
Craig’s review of St. Martin-in-the-Fields – “St. Martin-in-the-Fields is famous for helping out the homeless, and whenever you come in here you'll find a few of them kipping in the pews. There are two guys in here at the moment, gently resting their heads against the stone cold columns. The rain is knocking on the window and they've still got their hoods zipped up. I suppose when you're homeless you expect it to… continued”
Tchaikovsky and Szymanowski — Barbican Hall – 25 Oct 2018 – The London Symphony Orchestra will be performing some classical music by Tchaikovsky and Szymanowski at Barbican Hall.
Shostakovich, Kodaly and MacMillan — Barbican Hall – 1 Nov 2018 – The London Symphony Orchestra will be performing some classical music by Shostakovich, Kodaly and MacMillan at Barbican Hall.
BBC Symphony Orchestra — Music of Poland – 2 Nov 2018 – Michal Nesterowicz and the BBC Symphony Orchestra will be performing some classical music from Poland at Barbican Hall.
Mozart’s Requiem at St Paul’s Cathedral – 2 Nov 2018 – The Cathedral Choir and the City of London Sinfonia will be performing Mozart's Requiem at St Pauls Cathedral on All Souls' Day
Shostakovich and James MacMillan — Barbican Hall – 4 Nov 2018 – The London Symphony Orchestra will be performing some classical music by Shostakovich and James MacMillan at Barbican Hall.
Faure’s Requiem on the centenary of Armistice Day – 6 Nov 2018 – Listen to a performance of Faure's Requiem at Westminster Abbey on the 100th anniversary of Armistice Day.
Haydn, Bartok and Ligeti — London Symphony Orchestra – 11 Nov 2018 – The London Symphony Orchestra will be performing some classical music by Haydn, Bartok and Ligeti at Barbican Hall.
Here are some more free events in London if you want a cheap day out
If you enjoy St. Martin-in-the-Fields then you might like to visit National Gallery (you can walk it in less than 2 mins), National Portrait Gallery (you can walk it in less than 2 mins) and Trafalgar Square (you can walk it in less than 2 mins)
Disclaimer: Event details can change at short notice and you should reconfirm everything before making plans