# minimumLedgerSlot

> Returns the oldest slot the region's ledger holds.

Source: https://docs.constant-k.com/rpc/http/minimumledgerslot/

`minimumLedgerSlot` returns the oldest slot the region's ledger holds, and the value rises as old data is pruned. That slot is the lower bound for `getTransaction`, `getSignaturesForAddress` and similar calls. `getBlock` can return older blocks through [Cube Runner](/cube-runner/). See [`getFirstAvailableBlock`](/rpc/http/getfirstavailableblock/).

- Transport: HTTP, JSON-RPC 2.0 `POST` to `https://rpc-newyork.constant-k.com/?api-key=YOUR_API_KEY` (New York) or `https://rpc-frankfurt.constant-k.com/?api-key=YOUR_API_KEY` (Frankfurt) or `https://rpc-amsterdam.constant-k.com/?api-key=YOUR_API_KEY` (Amsterdam). The key also works as an `x-api-key` header.
- Category: Slots & Epochs
- Availability: All plans

## Parameters

None.

## Result

- `result` (integer, optional): The oldest slot the region's ledger holds.

## Example: Get the oldest retained ledger slot

Request:

```bash
curl "https://rpc-newyork.constant-k.com/?api-key=YOUR_API_KEY" \
  -X POST \
  -H "Content-Type: application/json" \
  -d '{ "jsonrpc": "2.0", "id": 1, "method": "minimumLedgerSlot" }'
```

Response:

```json
{
  "jsonrpc": "2.0",
  "result": 447896371,
  "id": 1
}
```

## Notes

- Each region's ledger is a rolling window of recent history, and this value marks where it starts. History calls for older slots fail rather than return empty or `null`.
- A value read once at startup goes stale during a long backward walk through history.