meaning of landing in register lease deed

You should post the paragraph so that we can answer it properly after reading it thoroughly. 

In consideration of the rent hereby reserved and the performance of the covenants on the part of the lesse hereinafter contained the lessor both hereby demise unto the lesse all that the portion on the ground floor admeasuring 1498 sq. Ft of the lessor's building situated at tower road mangrol and constructed on land more particularly described in the schedule here under written /and which said poruon is show on the plan therof hereto annexed and is delineated thereon by red colored boundary line. Together with the use of fittings and fixtures, the waters closets lavatories and other convenience in the said portion of ground floor hereby let and together also with the right for the lessee, its servants,employees,visitors, customers and all other person's authorised by the lessee to use in common with the lessor and the tenants and occupiers of other portions of the said building and all other persons authorised by the lessor the entrance, doorways, entrance halls staircases, landing, lobbies and passage in the said building leading to and from the said portion of the ground floor hereby let for the purpose of ingress there to and ingress therefrom to hold the demised premises unto the lessee from 1-April-2009.