Hajj is 1 of the 5 pillars of Islam. The Kingdom of Saudi Arabia has been privileged to host this event, which brings close to 2 million pilgrims from all over the world every year. During this holy ritual, the Muslims gather in Makkah before starting the journey. Recorded temperatures during the Hajj time is in the range between 37 degrees C and 45 degrees C. Overcrowding and the hot climate subject the pilgrims to environmental and health hazards. Dermatologic conditions, whether exacerbations of preexisting disease or the occurrence of new ones, account for 4.5% to 5.5% of all diseases seen during the 3-week periods of the Hajj. An overview of the mission of Hajj will be presented with an in-depth systematic review of dermatologic diseases seen at local hospitals in Makkah. Because the skin is the largest body organ and is the frontier defense for many environmental challenges, skin problems during the Hajj journey are not uncommon. The degree of heat and humidity may lead to exacerbation of preexisting cutaneous diseases or the occurrence of new ones. Overcrowding and poor hygiene also contribute to a myriad of infections: viral, bacterial, fungal, and/or parasitic. Skin diseases during Hajj can be divided into 2 broad categories, infectious and non-infectious. Unfortunately, despite the magnitude of Hajj and its existence for centuries, only a few reports and studies have been published about skin diseases. Preventative measures such as sunscreens, umbrellas, and protective footwear should be encouraged. The spread of cutaneous infections (fungal, viral, and bacterial) may be reduced with proper pretravel counseling and use of proper therapy.