In the Middle Ages, towers were used as fortified residences of the wealthy, or strategic military outposts. But these buildings still capture our imagination in the 21st century. Here are some cool tower houses, converted from historic towers, or built in the last few years as modern reinterpretations.

A modern home in Joachimstal, Germany, converted from a water tower

(via AcidCow)

Clocktower of One Main Street in Brooklyn, New York

And it's for sale for only $18 million!

(via Corcoran)

The Glen Lake Tower, by Balance Associates Architect in Michigan, built in 2011

(via ArchDaily)

A fire tower converted into a home, Poland

(via Wikimedia Commons)

An eleven-story home in Sir Christopher Wren's Christ Church Tower in London, UK, by Boyarsky Murphy Architects, 2007

The iconic church completed in 1687 was almost completely destroyed by German bombs during WWII: only the tower and four main walls survived the air raids.

(via Wikimedia Commons and Boyarsky Murphy Architects)

The Wicklow Head Lighthouse, Dunbur Head, Ireland, built in 1781, available to rent

(via Irish Landmark Trust)

Up in the Trees, a vacation house by GLUCK+ in Upstate New York, 2012

(via GLUCK+)

The House in the Clouds, built in 1923, Thorpeness, Suffolk, UK

The former water tower has 5 bedrooms, 3 bathrooms, stands in a middle of a one acre private ground and available for rent!

(via Karen Roe and House In The Clouds)

Pixel Im Turm, a hotel in the city tower of Enns, Austria, built in 1564

(via Turmhotel)

The 130 ft (40 m) high Munstead Water Tower, near Guildford, UK

This brick tower with 64 windows was erected in 1898, and used for seventy years. It was bought by in 1989 by Elspeth Beard from Elspeth Beard Architects and renovated the whole six-level structure.

There are now 88 steps to the kitchen, 116 to the living room and 142 steps to the roof.

(via Elspeth Beard Architects)

The Water Tower, by 1st Option, 2013

(via 1st Option and Treehugger)

Helen's Tower, Ireland, designed by William Burn and built constructed between 1848 and 1850

(via Irish Landmark Trust)

Mountain Cabin, by Marte.Marte Architekten in Laterns, Austria, 2011

(via ArchDaily)