Slightly off the radar art collection unless you are a real gallery buff.
Often overshadowed in the crowded museum spotlight for first time London visitors, the Wallace is a fantastic—and free, plus Soho-adjacent—showcase of more than 5,000 pieces from the 15th to 19th centuries, with especially strong holdings from 18th century France, and works from Old Masters including Rembrandt, Rubens, Van Dyck, Titian and Velázquez. Temporary exhibitions (like the recently completed Male Nude show) are often very gay-friendly, and the museum is also the site of an annual lecture during LGBT History Month in February.
Located just behind Selfridges not only does the Wallace Collection have a wonderful collection of art and antiquities but the lovely winter garden is worth a visit on its own.This is a real Londonder's secret as it's usually quiet during the week and a place where many thinkers come to centre themselves surrounded by the collection.It's also very near New Bond Street and Selfridges so a good place to come before or after hitting the shops.
Off the beaten path, but one of the best collections of old armour (European and Asian) in the City.
This shows the collection of two very avid collectors, a father and son, who amassed a world famous fine and decorative arts objects from the 15th to the 19th centuries. Particularly excellent French 18th-century paintings, furniture, arms & armour, porcelain and Old Master paintings arranged into 25 galleries in what used to be their home.