The ianVisits guide to April's unusual events, tours, lectures and exhibitions happening around London.
Saturday 27th April
Normally you need to pay to visit the gardens, but on a few weekends a year, the gardens are free to visit.
10am to 4pm
East Molesey
The Chelsea Physic Garden will have over 30 stalls selling plants, which gives you both a chance to buy a plant and to visit the Physic Garden for free.
10am to 5pm
Chelsea
£22.00
A weekend of computer games. W.A.S.D is the central playable and interactive feature of London Games Festival.
10am to 6pm
Whitechapel
The two-day festival includes 100+ vintage fashion traders, rare classic cars and more.
10am to 6pm
Kings Cross
The Museum's depot in Acton will be open for three days, giving you the opportunity to explore our collections store, with its treasure trove of over 320,000 objects.
10:30am to 5pm
Acton
An exhibition of quilts to celebrate this SE London quilting group's 25th anniversary.
10:30am to 4pm
Lewisham
The counter-cultural publishing house presents an evening of eclectic authors, artists and musicians, including Jarvis Cocker, Sheena Patel and Musa Okwonga.
Starts at 7:30pm
Southwark
More London events on Saturday 27th April
Sunday 28th April
Normally you need to pay to visit the gardens, but on a few weekends a year, the gardens are free to visit.
10am to 4pm
East Molesey
The two-day festival includes 100+ vintage fashion traders, rare classic cars and more.
10am to 6pm
Kings Cross
The Museum's depot in Acton will be open for three days, giving you the opportunity to explore our collections store, with its treasure trove of over 320,000 objects.
10:30am to 5pm
Acton
A WW2-era history attraction that's open to the public once a month.
10:30am to 4pm
Watford
Explore numerous stalls selling letterpress supplies, type and ornaments, paper, printed items, second-hand books and type specimens and lots more inky goodness.
11am to 4pm
City of London
Once a month, the oldest building in Hackney, St Augustine's Tower is open, so you can climb up to the top.
2pm to 4:30pm
Hackney
Agnes Arnold-Forster blends neuroscience and psychology with the history of medicine and emotions to explore the evolution of nostalgia.
3pm to 4:30pm
Holborn
More London events on Sunday 28th April
Monday 29th April
A guided tour of the unique and historic Stationers' Hall in the City of London.
11am to 12:30pm
City of London
This panel debate will bring together a diverse group of policy-makers, senior infrastructure professionals, academics and other experts to debate the topic.
6pm to 8pm
Pimlico
Boyajian's star, a faint and unprepossessing presence in the constellation of Cygnus, attracted astronomers' attention when it began to flicker alarmingly.
7pm to 8pm
Holborn
More London events on Monday 29th April
Tuesday 30th April
£8.00
The UCL Institute of Healthcare Engineering presents a showcase of the latest breakthroughs in health tech.
5pm to 6:30pm
Euston
Can a flower make you feel hope? Explore the relationship between art and emotion as we look at pictures from the RHS & Tate art collections
6:30pm to 8pm
Pimlico