Climb these towers during Open House weekend for secret views of London

Get access to great London views that are often off-limits to the public at this weekend’s city-wide festival of architecture, Open House

St Mary’s, Hornsey

Visit the oldest building in Hornsey, the last remnant of a medieval parish, surrounded by a garden of remembrance. The free Open House tour will get you access to all the best bits – the crypt, the ringing room (sadly no bells, they were ripped out and melted down in the late 1960s) but really, it’s all about the rooftop, which looks right across north London to Alexandra Palace. High St Hornsey, N8 7NT. Hornsey rail. Sun Sep 22, 2pm-5pm. Tours every 15 mins.

Photograph: FORM studio

Shad Thames Water Tower

Have a nosey around this swanky loft apartment contained in a narrow nineteenth-century warehouse building. At the tippity top, you’ll find a roof terrace constructed inside a redundant water tank. Standing on its platform will make you feel like a pirate peering at the Shard and Tower Bridge from your crows’ nest. Sun Sep 22, 10am-4.15pm. Pre-book only on 020 7407 3336.

Severndroog Castle

Spend the day at well-known gothic castle Severndroog, a 60-foot high triangular tower right in the middle of the ancient Oxleas Wood. Lady Anne James built the castle in the late eighteenth century in memory of her husband, Sir William, to commemorate his supposed destruction of a ‘pirate fortress’ – Suvarnadurg – near Goa (in fact, they were not pirates at all, it was more of a colonial invasion). Dodgy history aside, it has some good points, like the viewing platform, perched on a castle turret, which has a 360-degree view of the London skyline. And you get to see Oxleas in all its crunchy autumn amber glory. Castle Wood, Shooters Hill, SE18 3RT. Eltham rail. Sun Sep 22, 11am-4pm. Expect long queues.  

St Augustine’s Tower

Hornsey’s tower has got some competition from St Augustine’s, which was also part of a medieval chapel (the oldest building in Hackney: built in 1292, and named by the Knights Templar). Aside from its old age, it has a big dusty church bell, a clock tower and some gasp-worthy views of the City to be seen between its ancient stone walls. Mare St, E8 1HR. Hackney Central Overground. Sat Sep 21-Sun Sep 22, 11am-5pm. 

Seager Place, Distillery Tower

New developments loom over our streets like Bond villain HQs, reflecting the sunlight off their long glass jackets. Seager Place, which stands 27 floors tall on the site of an old gin distillery, is in this camp. But whatever you think of the outside, it’s worth checking out the panoramic London scenes from the observation deck on the inside. You’ll be able to spot The O2, Greenwich Observatory, Croydon and Crystal Palace from your villainous vantage point. 1 Mill Lane, SE8 4HN. Deptford Bridge rail. Sat Sep 21-Sun Sep 22, 10am-5pm.

More than 800 London buildings are participating in Open House festival this weekend (Saturday September 21-Sunday September 22). Here are some of our highlights. 

Can’t hack the queues? Catch the final weekend of London Design Festival instead.