Al Hayl Castle, Heritage fortress in Wadi Al Hayl, United Arab Emirates.

Al Hayl Castle is a mud-brick and plaster fortress standing at the foot of the Hajar Mountains in a wadi valley, combining residential quarters with a central watchtower. The layout shows how different parts of the structure served both as a home and as a defensive installation.

Sheikh Abdullah bin Hamdan Al Sharqi built Al Hayl Fort in 1932, and it served as his principal residence for about two decades until he moved to a house in Mirbah in 1958. The fortified house, mosque, majlis and watchtower were raised by the Bin Shamal family of builders, who also worked in Kalba and Fujairah, together with a builder named Bin Shambi. The watchtower first housed his younger brother Suhail, who later moved to Wadi Furfar.

The fort's name comes from the village of Al Hayl on the wadi of the same name, settled by the Kunud and Jalajilah tribes; Lorimer counted about ten houses there in 1908. The site was restored by Fujairah's Tourism and Antiquities Authority in 2009, and the old village buildings around the fort have been rebuilt.

The fort sits in Wadi Hayl west of Fujairah, reached by a track off the road along the wadi; the restored village and the watchtower on the ridge above are visited on foot over uneven stone and steps. The Fujairah Tourism and Antiquities Authority carried out a full restoration of the site in 2009. Ground in the wadi is a seasonal watercourse, so avoid the bed after rain.

The watchtower was first built as a home for Sheikh Abdullah's younger brother Suhail, who later moved to a house in Wadi Furfar. The fort is often called a summer house, though it stayed the Sheikh's residence until he moved to Mirbah in 1958.