Masjid Aisha, located in the area of Taneem approximately 7 km northwest of Mescid-i Haram, is the nearest Miqat point outside the Haram boundary (Hil). It is named after Aisha (may Allah be pleased with her), who was instructed by Hz. Peygamber (sallallahu aleyhi ve sellem) through her brother Abdur-Rahman to go to Taneem to enter Ihram for her Umre during the Farewell Hac.
You need to go to Taneem if you are already inside Mekke (within the Haram boundary) and wish to perform a new Umre. Since Ihram for Umre must be entered from outside the Haram boundary, you cannot simply make the intention from your hotel in Mekke. Taneem/Masjid Aisha is the closest and most convenient exit point for this purpose. Other options include going to Ja'ranah or Hudaybiyah, but Taneem is by far the most popular due to proximity.
The cami has modern facilities including: ablution areas, namaz spaces, separate sections for men and women to change into Ihram garments, and shops selling Ihram cloths and supplies. Taxis from the Haram area to Masjid Aisha are readily available — the trip takes about 15-20 minutes. Many Hac/Umre operators arrange group transport to Taneem for those wishing to perform a second Umre. Upon arriving at Taneem, perform gusul if possible, change into Ihram, make your niyyah for Umre, begin the Telbiye, and return to the Haram for Tavaf and Say.