shoe-leather

Short definition from Wiktionary

Noun

1. 1
   Leather that is used to make shoes.
2. 2
   Leather from which shoes are made that is worn out through walking.
3. 3
   The sweat of one's brow; effort; investigatory effort.
4. 4
   Tough meat, especially cheap meat.
5. 5
   Alternative form of shoe-leather.

Adjective

1. 1
   Basic, old-fashioned or traditional; specifically (journalism) shoe-leather journalism or shoe-leather reporting: journalism involving walking from place to place observing things and speaking to people, rather than sitting indoors at a desk.